Add missing #include's to cctype when using isdigit/alpha/etc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192519 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/FileCheck/FileCheck.cpp b/utils/FileCheck/FileCheck.cpp
index 43e8c79..77721f9 100644
--- a/utils/FileCheck/FileCheck.cpp
+++ b/utils/FileCheck/FileCheck.cpp
@@ -29,6 +29,7 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/system_error.h"
 #include <algorithm>
+#include <cctype>
 #include <map>
 #include <string>
 #include <vector>