Add an anchor to the android platform regex

Summary: This prevents android from matching in the middle of a platform.

Reviewed By: gkassabli

Differential Revision: D4306164

fbshipit-source-id: 7f62a6a017724f8f6741d3e53b5fbe0650c8c88e

lib/fb/BUCK

@@ -11,7 +11,7 @@ prebuilt_cxx_library(
   name = 'ndklog',
   header_only = True,
   exported_platform_linker_flags = [
-    ('android.*', ['-llog']),
+    ('^android.*', ['-llog']),
   ],
   visibility = [YOGA_ROOT],
 )