Rename modulesAddedWall to modulesWarningsAllowed

MODULES_ADDED_WALL is deceiving and it actually meant which modules are
allowed to have warnings (do not automatically append -Werror flag).

Test: presubmit
Bug: 233183337
Change-Id: Ia2eb972d3d76ba245840f9872cbcc66d2894dab3
diff --git a/core/binary.mk b/core/binary.mk
index 665270e..3f32fa9 100644
--- a/core/binary.mk
+++ b/core/binary.mk
@@ -1506,7 +1506,7 @@
         ifeq (,$(strip $(call find_warning_allowed_projects,$(LOCAL_PATH))))
           my_cflags := -Wall -Werror $(my_cflags)
         else
-          $(eval MODULES_ADDED_WALL := $(MODULES_ADDED_WALL) $(LOCAL_MODULE_MAKEFILE):$(LOCAL_MODULE))
+          $(eval MODULES_WARNINGS_ALLOWED := $(MODULES_USING_WNO_ERROR) $(LOCAL_MODULE_MAKEFILE):$(LOCAL_MODULE))
           my_cflags := -Wall $(my_cflags)
         endif
       endif