Add mainline dev certificate dir to config

Bug: 33691272
Test: build
Change-Id: Iea4d96ab9c58a1be6d25aff4c0cf91cfc097470e
diff --git a/core/config.mk b/core/config.mk
index bf3966a..8082831 100644
--- a/core/config.mk
+++ b/core/config.mk
@@ -803,6 +803,7 @@
 else
   MAINLINE_SEPOLICY_DEV_CERTIFICATES := $(dir $(DEFAULT_SYSTEM_DEV_CERTIFICATE))
 endif
+.KATI_READONLY := MAINLINE_SEPOLICY_DEV_CERTIFICATES
 
 BUILD_NUMBER_FROM_FILE := $$(cat $(SOONG_OUT_DIR)/build_number.txt)
 BUILD_DATETIME_FROM_FILE := $$(cat $(BUILD_DATETIME_FILE))
diff --git a/core/soong_config.mk b/core/soong_config.mk
index e975d8a..28ceebd 100644
--- a/core/soong_config.mk
+++ b/core/soong_config.mk
@@ -94,6 +94,7 @@
 $(call add_json_list, AAPTPrebuiltDPI,                   $(PRODUCT_AAPT_PREBUILT_DPI))
 
 $(call add_json_str,  DefaultAppCertificate,             $(PRODUCT_DEFAULT_DEV_CERTIFICATE))
+$(call add_json_str,  MainlineSepolicyDevCertificates,   $(MAINLINE_SEPOLICY_DEV_CERTIFICATES))
 
 $(call add_json_str,  AppsDefaultVersionName,            $(APPS_DEFAULT_VERSION_NAME))