[driver] -mkernel implies -fno-common, so claim the arg to avoid an unused
argument warning.
Part of rdar://11120518

llvm-svn: 153470
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index 4a69fc5..665a3aa 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -2401,6 +2401,7 @@
       Args.hasArg(options::OPT_fapple_kext)) {
     if (!Args.hasArg(options::OPT_fcommon))
       CmdArgs.push_back("-fno-common");
+    Args.ClaimAllArgs(options::OPT_fno_common);
   }
 
   // -fcommon is default, only pass non-default.