Add macro to support prebuilt vendor_vboot.img

There are marcos support to link prebuilt images and generate AVB images
in "make"/"make dist" flow. Currently defined marcos only cover boot.img
/init_boot.img/vendor.img and so on, missing the vendor_boot.img.
Appending a marco for prebuilt vendor_boot.img to work like other
prebuilt images.

Test: manual
Build pass in "make" and "make dist" flow and boot up with AVB

Change-Id: I7b296f82e57e8f71a0757d872d35ac27a8d2ecbe
Signed-off-by: chunhui dai <chunhuid@amazon.com>
diff --git a/core/Makefile b/core/Makefile
index 823d32e..61b4cb6 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1674,6 +1674,30 @@
 $(call declare-1p-container,$(INSTALLED_VENDOR_BOOTIMAGE_TARGET),)
 $(call declare-container-license-deps,$(INSTALLED_VENDOR_BOOTIMAGE_TARGET),$(INTERNAL_VENDOR_RAMDISK_TARGET) $(INSTALLED_DTB_IMAGE_TARGET) $(INTERNAL_VENDOR_RAMDISK_FRAGMENT_TARGETS) $(INTERNAL_VENDOR_BOOTCONDIG_TARGET),$(PRODUCT_OUT)/:/)
 VENDOR_NOTICE_DEPS += $(INSTALLED_VENDOR_BOOTIMAGE_TARGET)
+
+else # BUILDING_VENDOR_BOOT_IMAGE not defined, use prebuilt image
+
+ifdef BOARD_PREBUILT_VENDOR_BOOTIMAGE
+INTERNAL_PREBUILT_VENDOR_BOOTIMAGE := $(BOARD_PREBUILT_VENDOR_BOOTIMAGE)
+INSTALLED_VENDOR_BOOTIMAGE_TARGET := $(PRODUCT_OUT)/vendor_boot.img
+
+ifeq ($(BOARD_AVB_ENABLE),true)
+$(INSTALLED_VENDOR_BOOTIMAGE_TARGET): $(INTERNAL_PREBUILT_VENDOR_BOOTIMAGE) $(AVBTOOL) $(BOARD_AVB_VENDOR_BOOT_KEY_PATH)
+	cp $(INTERNAL_PREBUILT_VENDOR_BOOTIMAGE) $@
+	chmod +w $@
+	$(AVBTOOL) add_hash_footer \
+	    --image $@ \
+	    $(call get-partition-size-argument,$(BOARD_VENDOR_BOOTIMAGE_PARTITION_SIZE)) \
+	    --partition_name vendor_boot $(INTERNAL_AVB_VENDOR_BOOT_SIGNING_ARGS) \
+	    $(BOARD_AVB_VENDOR_BOOT_ADD_HASH_FOOTER_ARGS)
+else
+$(INSTALLED_VENDOR_BOOTIMAGE_TARGET): $(INTERNAL_PREBUILT_VENDOR_BOOTIMAGE)
+	cp $(INTERNAL_PREBUILT_VENDOR_BOOTIMAGE) $@
+
+endif # BOARD_AVB_ENABLE
+$(call declare-1p-container,$(INSTALLED_VENDOR_BOOTIMAGE_TARGET),)
+$(call declare-container-license-deps,$(INSTALLED_VENDOR_BOOTIMAGE_TARGET),$(INTERNAL_PREBUILT_VENDOR_BOOTIMAGE),$(PRODUCT_OUT)/:/)
+endif # BOARD_PREBUILT_VENDOR_BOOTIMAGE
 endif # BUILDING_VENDOR_BOOT_IMAGE
 
 # -----------------------------------------------------------------
@@ -6661,6 +6685,10 @@
 	@# If breakpad symbols have been generated, add them to the zip.
 	$(hide) cp -R $(TARGET_OUT_BREAKPAD) $(zip_root)/BREAKPAD
 endif
+ifdef BOARD_PREBUILT_VENDOR_BOOTIMAGE
+	$(hide) mkdir -p $(zip_root)/IMAGES
+	$(hide) cp $(INSTALLED_VENDOR_BOOTIMAGE_TARGET) $(zip_root)/IMAGES/
+endif
 ifdef BOARD_PREBUILT_VENDORIMAGE
 	$(hide) mkdir -p $(zip_root)/IMAGES
 	$(hide) cp $(INSTALLED_VENDORIMAGE_TARGET) $(zip_root)/IMAGES/