[DebugInfo] Fix some Clang-tidy modernize-use-using and Include What You Use warnings; other minor fixes (NFC).

llvm-svn: 306169
diff --git a/llvm/lib/DebugInfo/MSF/MSFCommon.cpp b/llvm/lib/DebugInfo/MSF/MSFCommon.cpp
index fdab788..1facf5e 100644
--- a/llvm/lib/DebugInfo/MSF/MSFCommon.cpp
+++ b/llvm/lib/DebugInfo/MSF/MSFCommon.cpp
@@ -1,4 +1,4 @@
-//===- MSFCommon.cpp - Common types and functions for MSF files -*- C++ -*-===//
+//===- MSFCommon.cpp - Common types and functions for MSF files -----------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -9,6 +9,10 @@
 
 #include "llvm/DebugInfo/MSF/MSFCommon.h"
 #include "llvm/DebugInfo/MSF/MSFError.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/Error.h"
+#include <cstdint>
+#include <cstring>
 
 using namespace llvm;
 using namespace llvm::msf;