ASoC: SOF: loader: add dynamic debug trace

We currently have no trace referring to the firmware path, add a trace
to help debug cases where the wrong file might be used.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200107160840.1524-3-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/loader.c

@@ -487,6 +487,9 @@ int snd_sof_load_firmware_raw(struct snd_sof_dev *sdev)
 	if (ret < 0) {
 		dev_err(sdev->dev, "error: request firmware %s failed err: %d\n",
 			fw_filename, ret);
+	} else {
+		dev_dbg(sdev->dev, "request_firmware %s successful\n",
+			fw_filename);
 	}
 
 	kfree(fw_filename);