greybus: Use valid control pointer while freeing memory

While releasing memory during error path exit, invalid memory pointer
was used for dapm_routes. Use a valid one.
Signed-off-by: NVaibhav Agarwal <vaibhav.agarwal@linaro.org>
Reviewed-by: NMark Greer <mgreer@animalcreek.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/audio_topology.c

@@ -1317,7 +1317,7 @@ static int gbaudio_tplg_process_routes(struct gbaudio_module_info *module,
 	return 0;
 
 error:
-	devm_kfree(module->dev, dapm_routes);
+	devm_kfree(module->dev, module->dapm_routes);
 	return ret;
 }