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/lib/Object/COFFObjectFile.cpp b/lib/Object/COFFObjectFile.cpp
index 67b8e6b..3d1e62e 100644
--- a/lib/Object/COFFObjectFile.cpp
+++ b/lib/Object/COFFObjectFile.cpp
@@ -18,6 +18,7 @@
 #include "llvm/ADT/Triple.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
+#include <cctype>
 
 using namespace llvm;
 using namespace object;