Add METADATA to libcore: GPL+LGPL=RESTRICTED

Bug: 68860345
Bug: 69058154
Bug: 151953481

Test: no code changes
Change-Id: I95d890944030b718b7ea7330af80f036408d2d6b
diff --git a/METADATA b/METADATA
new file mode 100644
index 0000000..6d8601b
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,3 @@
+third_party {
+  license_type: RESTRICTED
+}