Revert "Add system staging dir stamp file for bazel sandwich"

Revert submission 2651299-bazel_sandwich

Reason for revert: b/293883239, checking if this breaks the build.

Reverted changes: /q/submissionid:2651299-bazel_sandwich

Change-Id: I40661772148434adf5fbec9568b4c303ff7eaf1c
diff --git a/core/Makefile b/core/Makefile
index d23ab19..dcec2e5 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -3355,10 +3355,6 @@
     $(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)"