Use the simpler version of sys::fs::remove when possible.

llvm-svn: 198958

llvm/lib/Support/GraphWriter.cpp

@@ -87,8 +87,7 @@ ExecGraphViewer(StringRef ExecPath, std::vector<const char*> &args,
       errs() << "Error: " << ErrMsg << "\n";
       return false;
     }
-    bool Existed;
-    sys::fs::remove(Filename, Existed);
+    sys::fs::remove(Filename);
     errs() << " done. \n";
   }
   else {