Hide -global-merge option.

llvm-svn: 138540
diff --git a/llvm/lib/Target/ARM/ARMTargetMachine.cpp b/llvm/lib/Target/ARM/ARMTargetMachine.cpp
index 39552ac..78a6a43 100644
--- a/llvm/lib/Target/ARM/ARMTargetMachine.cpp
+++ b/llvm/lib/Target/ARM/ARMTargetMachine.cpp
@@ -22,7 +22,7 @@
 using namespace llvm;
 
 static cl::opt<bool>
-EnableGlobalMerge("global-merge",
+EnableGlobalMerge("global-merge", cl::Hidden,
                   cl::desc("Enable global merge pass"),
                   cl::init(true));