Fix config.test for assimp

Change-Id: I1b139ae7fb489bbb84486360ea6abe1404441bac
Reviewed-by: Christian Strømme <christian.stromme@qt.io>

config.tests/assimp/main.cpp

@@ -48,7 +48,7 @@ int main(int , char **)
 
   // Check for something that was set in a recent version
   aiMaterial aiM;
-  (void)ai.GetName();
+  (void)aiM.GetName();
 
   return 0;
 }