Revert "Revert "Add system staging dir stamp file for bazel sand..."

Revert submission 2685589-revert-2651299-bazel_sandwich-TVXWOASJNU

Reason for revert: It was not the cause of b/293883239

Reverted changes: /q/submissionid:2685589-revert-2651299-bazel_sandwich-TVXWOASJNU

Change-Id: I98ca2be7490a4e38d35e4e640a0d027711b67030
diff --git a/core/Makefile b/core/Makefile
index dcec2e5..d23ab19 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -3355,6 +3355,10 @@
     $(call intermediates-dir-for,PACKAGING,systemimage)
 BUILT_SYSTEMIMAGE := $(systemimage_intermediates)/system.img
 
+# Used by the bazel sandwich to request the staging dir be built
+$(systemimage_intermediates)/staging_dir.stamp: $(FULL_SYSTEMIMAGE_DEPS)
+	touch $@
+
 # $(1): output file
 define build-systemimage-target
   @echo "Target system fs image: $(1)"