tests: Use -ffreestanding when including stdint.h, to avoid platform dependencies.

llvm-svn: 113301
diff --git a/clang/test/Lexer/digraph.c b/clang/test/Lexer/digraph.c
index b8a99bb..cf6e478 100644
--- a/clang/test/Lexer/digraph.c
+++ b/clang/test/Lexer/digraph.c
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -verify < %s
+// RUN: %clang_cc1 -fsyntax-only -verify -ffreestanding %s
 
 %:include <stdint.h>