[msf] Rename Msf to MSF.

In a previous patch, it was suggested to use all caps instead of
rolling caps for initialisms, so this patch changes everything
to do this.

llvm-svn: 277190
diff --git a/llvm/lib/DebugInfo/PDB/Raw/ModStream.cpp b/llvm/lib/DebugInfo/PDB/Raw/ModStream.cpp
index 25bb9d1..3810b29 100644
--- a/llvm/lib/DebugInfo/PDB/Raw/ModStream.cpp
+++ b/llvm/lib/DebugInfo/PDB/Raw/ModStream.cpp
@@ -9,7 +9,7 @@
 
 #include "llvm/DebugInfo/PDB/Raw/ModStream.h"
 
-#include "llvm/DebugInfo/Msf/StreamReader.h"
+#include "llvm/DebugInfo/MSF/StreamReader.h"
 #include "llvm/DebugInfo/PDB/Raw/ModInfo.h"
 #include "llvm/DebugInfo/PDB/Raw/PDBFile.h"
 #include "llvm/DebugInfo/PDB/Raw/RawError.h"