Header guard canonicalization, clang part.

Modifications made by clang-tidy with minor tweaks.

llvm-svn: 215557
diff --git a/clang/lib/Driver/InputInfo.h b/clang/lib/Driver/InputInfo.h
index 4eedd22..b23ba57 100644
--- a/clang/lib/Driver/InputInfo.h
+++ b/clang/lib/Driver/InputInfo.h
@@ -7,8 +7,8 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef CLANG_LIB_DRIVER_INPUTINFO_H_
-#define CLANG_LIB_DRIVER_INPUTINFO_H_
+#ifndef LLVM_CLANG_LIB_DRIVER_INPUTINFO_H
+#define LLVM_CLANG_LIB_DRIVER_INPUTINFO_H
 
 #include "clang/Driver/Types.h"
 #include "llvm/Option/Arg.h"