Don't #include <stdio.h> when tests don't need it, or use clang instead of clang-cc when they do.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@89070 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/CodeGen/blocks-1.c b/test/CodeGen/blocks-1.c
index 5b639d1..ae5a74a 100644
--- a/test/CodeGen/blocks-1.c
+++ b/test/CodeGen/blocks-1.c
@@ -7,7 +7,7 @@
 // RUN: grep "i32 135)" %t | count 2
 // RUN: grep "_Block_object_assign" %t | count 10
 
-#include <stdio.h>
+int printf(const char *, ...);
 
 void test1() {
   __block int a;