Update intermediates dir of soong built system partition

Test: Previously failing OTA test now passes https://android-build.corp.google.com/builds/abtd/run/L04100030008317770
Change-Id: I23e6d2b953bd7dd66d7946fb1b699c69a7250f81
diff --git a/core/Makefile b/core/Makefile
index e106dad..1180073 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -6663,7 +6663,7 @@
 	@# Contents of the system image
 ifneq ($(SOONG_DEFINED_SYSTEM_IMAGE_PATH),)
 	$(hide) $(call package_files-copy-root, \
-	    $(SOONG_DEFINED_SYSTEM_IMAGE_BASE)/root/system,$(zip_root)/SYSTEM)
+	    $(SOONG_DEFINED_SYSTEM_IMAGE_BASE)/system/system,$(zip_root)/SYSTEM)
 else
 	$(hide) $(call package_files-copy-root, \
 	    $(SYSTEMIMAGE_SOURCE_DIR),$(zip_root)/SYSTEM)