Export ProductBuildVendorBootImage to soong

Also add a file list file for vendor_ramdisk to compare against the
soong-built one.

Bug: 377563622
Test: Presubmits
Change-Id: I1842f767c3e560de1d11e024a7c918542e31095d
diff --git a/core/Makefile b/core/Makefile
index 5e0d4df..92dd86d 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1654,6 +1654,8 @@
     $(ALL_DEFAULT_INSTALLED_MODULES))
 
 INTERNAL_VENDOR_RAMDISK_TARGET := $(call intermediates-dir-for,PACKAGING,vendor_boot)/vendor_ramdisk.cpio$(RAMDISK_EXT)
+vendor_ramdisk_intermediates :=$= $(call intermediates-dir-for,PACKAGING,vendor_ramdisk)
+$(eval $(call write-partition-file-list,$(vendor_ramdisk_intermediates)/file_list.txt,$(TARGET_VENDOR_RAMDISK_OUT),$(INTERNAL_VENDOR_RAMDISK_FILES)))
 
 # Exclude recovery files in the default vendor ramdisk if including a standalone
 # recovery ramdisk in vendor_boot.