Deprecate BOARD_GKI_SIGNING_* vars and build rules

These were for building and signing GKIs in the platform tree.
We are no longer building GKIs this way, so remove these dead build
rules.

Bug: 229701033
Test: presubmit
Change-Id: I0b807de1407988489e994ec5a0da282616ac1af1
diff --git a/core/Makefile b/core/Makefile
index 18f2c39..b93c321 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1158,7 +1158,7 @@
 
 BOARD_KERNEL_16K_BOOTIMAGE_PARTITION_SIZE := $(BOARD_BOOTIMAGE_PARTITION_SIZE)
 
-$(BUILT_BOOTIMAGE_16K_TARGET): $(MKBOOTIMG) $(AVBTOOL) $(INTERNAL_BOOTIMAGE_FILES) $(BOARD_AVB_BOOT_KEY_PATH) $(INTERNAL_GKI_CERTIFICATE_DEPS) $(BUILT_KERNEL_16K_TARGET)
+$(BUILT_BOOTIMAGE_16K_TARGET): $(MKBOOTIMG) $(AVBTOOL) $(INTERNAL_BOOTIMAGE_FILES) $(BOARD_AVB_BOOT_KEY_PATH) $(BUILT_KERNEL_16K_TARGET)
 	$(call pretty,"Target boot 16k image: $@")
 	$(call build_boot_from_kernel_avb_enabled,$@,$(BUILT_KERNEL_16K_TARGET))
 
@@ -1281,15 +1281,6 @@
 define build_boot_from_kernel_avb_enabled
   $(eval kernel := $(2))
   $(MKBOOTIMG) --kernel $(kernel) $(INTERNAL_BOOTIMAGE_ARGS) $(INTERNAL_MKBOOTIMG_VERSION_ARGS) $(BOARD_MKBOOTIMG_ARGS) --output $(1)
-  $(if $(BOARD_GKI_SIGNING_KEY_PATH), \
-    $(eval boot_signature := $(call intermediates-dir-for,PACKAGING,generic_boot)/$(notdir $(1)).boot_signature) \
-    $(eval kernel_signature := $(call intermediates-dir-for,PACKAGING,generic_kernel)/$(notdir $(kernel)).boot_signature) \
-    $(call generate_generic_boot_image_certificate,$(1),$(boot_signature),boot,$(BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS)) $(newline) \
-    $(call generate_generic_boot_image_certificate,$(kernel),$(kernel_signature),generic_kernel,$(BOARD_AVB_BOOT_ADD_HASH_FOOTER_ARGS)) $(newline) \
-    cat $(kernel_signature) >> $(boot_signature) $(newline) \
-    $(call assert-max-image-size,$(boot_signature),16 << 10) $(newline) \
-    truncate -s $$(( 16 << 10 )) $(boot_signature) $(newline) \
-    cat "$(boot_signature)" >> $(1))
   $(call assert-max-image-size,$(1),$(call get-hash-image-max-size,$(call get-bootimage-partition-size,$(1),boot)))
   $(AVBTOOL) add_hash_footer \
           --image $(1) \
@@ -1340,51 +1331,9 @@
   endif
 endif # BUILDING_VENDOR_BOOT_IMAGE == "" && BOARD_USES_GENERIC_KERNEL_IMAGE != true
 
-ifdef BOARD_GKI_SIGNING_KEY_PATH
-  # GKI boot images will not set system version & SPL value in the header.
-  # They can be set by the device manufacturer in the AVB properties instead.
-  INTERNAL_MKBOOTIMG_VERSION_ARGS :=
-else
-  INTERNAL_MKBOOTIMG_VERSION_ARGS := \
-    --os_version $(PLATFORM_VERSION_LAST_STABLE) \
-    --os_patch_level $(PLATFORM_SECURITY_PATCH)
-endif # BOARD_GKI_SIGNING_KEY_PATH
-
-# $(1): image target to certify
-# $(2): out certificate target
-# $(3): image name
-# $(4): additional AVB arguments
-define generate_generic_boot_image_certificate
-  rm -rf "$(2)"
-  mkdir -p "$(dir $(2))"
-  $(GENERATE_GKI_CERTIFICATE) $(INTERNAL_GKI_CERTIFICATE_ARGS) \
-    --additional_avb_args "$(4)" \
-    --name "$(3)" --output "$(2)" "$(1)"
-endef
-
-INTERNAL_GKI_CERTIFICATE_ARGS :=
-INTERNAL_GKI_CERTIFICATE_DEPS :=
-ifdef BOARD_GKI_SIGNING_KEY_PATH
-  ifndef BOARD_GKI_SIGNING_ALGORITHM
-    $(error BOARD_GKI_SIGNING_ALGORITHM should be defined with BOARD_GKI_SIGNING_KEY_PATH)
-  endif
-
-  INTERNAL_GKI_CERTIFICATE_ARGS := \
-    --key "$(BOARD_GKI_SIGNING_KEY_PATH)" \
-    --algorithm "$(BOARD_GKI_SIGNING_ALGORITHM)" \
-    --avbtool "$(AVBTOOL)"
-
-  # Quote and pass BOARD_GKI_SIGNING_SIGNATURE_ARGS as a single string argument.
-  ifdef BOARD_GKI_SIGNING_SIGNATURE_ARGS
-    INTERNAL_GKI_CERTIFICATE_ARGS += --additional_avb_args "$(BOARD_GKI_SIGNING_SIGNATURE_ARGS)"
-  endif
-
-  INTERNAL_GKI_CERTIFICATE_DEPS := \
-    $(GENERATE_GKI_CERTIFICATE) \
-    $(BOARD_GKI_SIGNING_KEY_PATH) \
-    $(AVBTOOL)
-
-endif
+INTERNAL_MKBOOTIMG_VERSION_ARGS := \
+  --os_version $(PLATFORM_VERSION_LAST_STABLE) \
+  --os_patch_level $(PLATFORM_SECURITY_PATCH)
 
 # Define these only if we are building boot
 ifdef BUILDING_BOOT_IMAGE
@@ -1404,17 +1353,17 @@
   $(call build_boot_from_kernel_avb_enabled,$(1),$(kernel))
 endef
 
-$(INSTALLED_BOOTIMAGE_TARGET): $(MKBOOTIMG) $(AVBTOOL) $(INTERNAL_BOOTIMAGE_FILES) $(BOARD_AVB_BOOT_KEY_PATH) $(INTERNAL_GKI_CERTIFICATE_DEPS)
+$(INSTALLED_BOOTIMAGE_TARGET): $(MKBOOTIMG) $(AVBTOOL) $(INTERNAL_BOOTIMAGE_FILES) $(BOARD_AVB_BOOT_KEY_PATH)
 	$(call pretty,"Target boot image: $@")
 	$(call build_boot_board_avb_enabled,$@)
 
 $(call declare-container-license-metadata,$(INSTALLED_BOOTIMAGE_TARGET),SPDX-license-identifier-GPL-2.0-only SPDX-license-identifier-Apache-2.0,restricted notice,$(BUILD_SYSTEM)/LINUX_KERNEL_COPYING build/soong/licenses/LICENSE,"Boot Image",boot)
-$(call declare-container-license-deps,$(INSTALLED_BOOTIMAGE_TARGET),$(INTERNAL_BOOTIMAGE_FILES) $(INTERNAL_GKI_CERTIFICATE_DEPS),$(PRODUCT_OUT)/:/)
+$(call declare-container-license-deps,$(INSTALLED_BOOTIMAGE_TARGET),$(INTERNAL_BOOTIMAGE_FILES),$(PRODUCT_OUT)/:/)
 
 UNMOUNTED_NOTICE_VENDOR_DEPS += $(INSTALLED_BOOTIMAGE_TARGET)
 
 .PHONY: bootimage-nodeps
-bootimage-nodeps: $(MKBOOTIMG) $(AVBTOOL) $(BOARD_AVB_BOOT_KEY_PATH) $(INTERNAL_GKI_CERTIFICATE_DEPS)
+bootimage-nodeps: $(MKBOOTIMG) $(AVBTOOL) $(BOARD_AVB_BOOT_KEY_PATH)
 	@echo "make $@: ignoring dependencies"
 	$(foreach b,$(INSTALLED_BOOTIMAGE_TARGET),$(call build_boot_board_avb_enabled,$(b)))
 
@@ -5525,7 +5474,6 @@
   fsck.erofs \
   fsck.f2fs \
   fs_config \
-  generate_gki_certificate \
   generate_verity_key \
   host_init_verifier \
   img2simg \
@@ -5810,11 +5758,6 @@
 	$(hide) echo 'recovery_mkbootimg_args=$(BOARD_RECOVERY_MKBOOTIMG_ARGS)' >> $@
 	$(hide) echo 'mkbootimg_version_args=$(INTERNAL_MKBOOTIMG_VERSION_ARGS)' >> $@
 	$(hide) echo 'mkbootimg_init_args=$(BOARD_MKBOOTIMG_INIT_ARGS)' >> $@
-ifdef BOARD_GKI_SIGNING_KEY_PATH
-	$(hide) echo 'gki_signing_key_path=$(BOARD_GKI_SIGNING_KEY_PATH)' >> $@
-	$(hide) echo 'gki_signing_algorithm=$(BOARD_GKI_SIGNING_ALGORITHM)' >> $@
-	$(hide) echo 'gki_signing_signature_args=$(BOARD_GKI_SIGNING_SIGNATURE_ARGS)' >> $@
-endif
 	$(hide) echo "multistage_support=1" >> $@
 	$(hide) echo "blockimgdiff_versions=3,4" >> $@
 ifeq ($(PRODUCT_BUILD_GENERIC_OTA_PACKAGE),true)