syntaxunified directive is a no-op for MachO writing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118287 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCMachOStreamer.cpp b/lib/MC/MCMachOStreamer.cpp
index 21f3002..6690618 100644
--- a/lib/MC/MCMachOStreamer.cpp
+++ b/lib/MC/MCMachOStreamer.cpp
@@ -149,6 +149,7 @@
 
 void MCMachOStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
   switch (Flag) {
+  case MCAF_SyntaxUnified:  return; // no-op here.
   case MCAF_SubsectionsViaSymbols:
     getAssembler().setSubsectionsViaSymbols(true);
     return;