[IROutliner] Move global namespace cl::opt inside llvm::

llvm/lib/Analysis/IRSimilarityIdentifier.cpp

@@ -23,11 +23,13 @@
 using namespace llvm;
 using namespace IRSimilarity;
 
+namespace llvm {
 cl::opt<bool>
     DisableBranches("no-ir-sim-branch-matching", cl::init(false),
                     cl::ReallyHidden,
                     cl::desc("disable similarity matching, and outlining, "
                              "across branches for debugging purposes."));
+} // namespace llvm
 
 IRInstructionData::IRInstructionData(Instruction &I, bool Legality,
                                      IRInstructionDataList &IDList)

llvm/lib/Transforms/IPO/IROutliner.cpp

@@ -36,7 +36,9 @@ using namespace IRSimilarity;
 
 // A command flag to be used for debugging to exclude branches from similarity
 // matching and outlining.
+namespace llvm {
 extern cl::opt<bool> DisableBranches;
+} // namespace llvm
 
 // Set to true if the user wants the ir outliner to run on linkonceodr linkage
 // functions. This is false by default because the linker can dedupe linkonceodr