Dont cast away const needlessly. Found by gcc48 -Wcast-qual.

llvm-svn: 163325
diff --git a/clang/lib/Analysis/ThreadSafety.cpp b/clang/lib/Analysis/ThreadSafety.cpp
index 90c407a..b3e97af 100644
--- a/clang/lib/Analysis/ThreadSafety.cpp
+++ b/clang/lib/Analysis/ThreadSafety.cpp
@@ -953,7 +953,7 @@
       return;
     }
     Dec->printName(llvm::errs());
-    llvm::errs() << "." << i << " " << ((void*) Dec);
+    llvm::errs() << "." << i << " " << ((const void*) Dec);
   }
 
   /// Dumps an ASCII representation of the variable map to llvm::errs()