Add missing standard headers. Patch by Joerg Sonnenberger!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122193 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp
index 40aa077..a171ba1 100644
--- a/lib/MC/MCAsmStreamer.cpp
+++ b/lib/MC/MCAsmStreamer.cpp
@@ -27,6 +27,7 @@
 #include "llvm/Target/TargetAsmBackend.h"
 #include "llvm/Target/TargetAsmInfo.h"
 #include "llvm/Target/TargetLoweringObjectFile.h"
+#include <cctype>
 using namespace llvm;
 
 namespace {