Add LOCAL_FULL_VINTF_FRAGMENTS to handle full path

Soong supports references to other modules for vintf_fragments property,
so full paths need to be passed from Soong to make rather than module
local paths.

Test: m droid
Bug: 184567830
Change-Id: Ia7f1cf977de8aeb08d41624277ff6231198222e5
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index faca97a..e2acb67 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -109,6 +109,7 @@
 LOCAL_FULL_LIBS_MANIFEST_FILES:=
 LOCAL_FULL_MANIFEST_FILE:=
 LOCAL_FULL_TEST_CONFIG:=
+LOCAL_FULL_VINTF_FRAGMENTS:=
 LOCAL_FUZZ_ENGINE:=
 LOCAL_FUZZ_INSTALLED_SHARED_DEPS:=
 LOCAL_GCNO_FILES:=