clang-format: Appease the buildbots by including climits.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@236995 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Format/FormatToken.cpp

@@ -18,6 +18,7 @@
 #include "clang/Format/Format.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/Debug.h"
+#include <climits>
 
 namespace clang {
 namespace format {