Mark mfcall.cpp as UNSUPPORTED: win32.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@335573 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/cfi/mfcall.cpp b/test/cfi/mfcall.cpp
index d101054..6e22e3f 100644
--- a/test/cfi/mfcall.cpp
+++ b/test/cfi/mfcall.cpp
@@ -1,3 +1,5 @@
+// UNSUPPORTED: win32
+
 // RUN: %clangxx_cfi -o %t %s
 // RUN: %expect_crash %run %t a
 // RUN: %expect_crash %run %t b