Makefiles: Remove query for CMAKE_OBJECT_NAME

it is not set.

Source/cmMakefileTargetGenerator.cxx

@@ -1207,9 +1207,7 @@ void cmMakefileTargetGenerator::WriteObjectsVariable(
        i != this->ExternalObjects.end(); ++i) {
     object =
       this->LocalGenerator->MaybeConvertToRelativePath(currentBinDir, *i);
-    *this->BuildFileStream << " " << lineContinue << "\n"
-                           << this->Makefile->GetSafeDefinition(
-                                "CMAKE_OBJECT_NAME");
+    *this->BuildFileStream << " " << lineContinue << "\n";
     *this->BuildFileStream << this->LocalGenerator->ConvertToQuotedOutputPath(
       i->c_str(), useWatcomQuote);
   }