[PM] Get rid of an unused variable in AnalysisManager::clear(IRUnitT&).

[silvas]

Please do this kind of cleanup with post-commit review in the future.

llvm/trunk/include/llvm/IR/PassManager.h

public:
   ///
   /// This doesn't invalidate but directly clears the results. It is useful
   /// when the IR is being removed and we want to clear out all the memory
   /// pinned for it.
   void clear(IRUnitT &IR) {
     if (DebugLogging)
       dbgs() << "Clearing all analysis results for: " << IR.getName() << "\n";
 
-    // Clear all the invalidated results associated specifically with this
-    // function.
-    SmallVector<AnalysisKey *, 8> InvalidatedIDs;
     auto ResultsListI = AnalysisResultLists.find(&IR);
     if (ResultsListI == AnalysisResultLists.end())
       return;
     // Clear the map pointing into the results list.
     for (auto &IDAndResult : ResultsListI->second)
       AnalysisResults.erase({IDAndResult.first, &IR});
 
     // And actually destroy and erase the results associated with this IR.