Remove -fwhole-program-vtables flags from librenderengine static library

-fwhole-program-vtables optimisation is not possible
for a static library, since at linking stage there are
other parts that are not LTO'ed.

Test: presubmit
Change-Id: I64bccf091fa62d91ca8e3bb9aa0658a0c99ca2d7
diff --git a/libs/renderengine/Android.bp b/libs/renderengine/Android.bp
index cc252d6..136ad0d 100644
--- a/libs/renderengine/Android.bp
+++ b/libs/renderengine/Android.bp
@@ -71,9 +71,6 @@
         "-fvisibility=hidden",
         "-Werror=format",
     ],
-    cppflags: [
-        "-fwhole-program-vtables", // requires ThinLTO
-    ],
     srcs: [
         ":librenderengine_sources",
         ":librenderengine_gl_sources",