MC/Mach-O: Move createMachObjectWriter into MCMachObjectWriter.h.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121971 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MachObjectWriter.cpp b/lib/MC/MachObjectWriter.cpp
index 96867e4..7c6e591 100644
--- a/lib/MC/MachObjectWriter.cpp
+++ b/lib/MC/MachObjectWriter.cpp
@@ -12,6 +12,7 @@
 #include "llvm/MC/MCAssembler.h"
 #include "llvm/MC/MCAsmLayout.h"
 #include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCMachObjectWriter.h"
 #include "llvm/MC/MCObjectWriter.h"
 #include "llvm/MC/MCSectionMachO.h"
 #include "llvm/MC/MCSymbol.h"