Add LOCAL_DONT_MERGE_MANIFESTS

Some modules have manifests that ManifestMerger doesn't like, and
don't need manifest merging.  Skip manifest merger if
LOCAL_DONT_MERGE_MANIFESTS is set.

Bug: 78447299
Test: m checkbuild
Change-Id: If1a58253c62e0194a6acfd79930b9bb10978abe5
diff --git a/core/clear_vars.mk b/core/clear_vars.mk
index 1a33153..8cc7c98 100644
--- a/core/clear_vars.mk
+++ b/core/clear_vars.mk
@@ -61,6 +61,7 @@
 LOCAL_DONT_CHECK_MODULE:=
 # Don't delete the META_INF dir when merging static Java libraries.
 LOCAL_DONT_DELETE_JAR_META_INF:=
+LOCAL_DONT_MERGE_MANIFESTS:=
 LOCAL_DPI_FILE_STEM:=
 LOCAL_DPI_VARIANTS:=
 LOCAL_DROIDDOC_ASSET_DIR:=