Disable this on mingw again.

I will investigate why it still fails, but for now this gets the bots green.

llvm-svn: 189807

clang/test/Driver/qa_override.c

@@ -1,6 +1,9 @@
 // RUN: env QA_OVERRIDE_GCC3_OPTIONS="#+-Os +-Oz +-O +-O3 +-Oignore +a +b +c xb Xa Omagic ^-###  " %clang %s -O2 b -O3 2>&1 | FileCheck %s
 // RUN: env QA_OVERRIDE_GCC3_OPTIONS="x-Werror +-mfoo" %clang -Werror %s -c -### 2>&1 | FileCheck %s -check-prefix=RM-WERROR
 
+// FIXME: It seems doesn't work with gcc-driver.
+// REQUIRES: clang-driver
+
 // CHECK: "-cc1"
 // CHECK-NOT: "-Oignore"
 // CHECK: "-Omagic"