ASoC: Intel: sof-rt5682: add a check for devm_clk_get

sof_audio_probe misses a check for devm_clk_get and may cause problems.
Add a check for it to fix the bug.
Signed-off-by: NChuhong Yuan <hslester96@gmail.com>
Acked-by: NPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20191017025044.31474-1-hslester96@gmail.comSigned-off-by: NMark Brown <broonie@kernel.org>

sound/soc/intel/boards/sof_rt5682.c

@@ -603,6 +603,15 @@ static int sof_audio_probe(struct platform_device *pdev)
 	/* need to get main clock from pmc */
 	if (sof_rt5682_quirk & SOF_RT5682_MCLK_BYTCHT_EN) {
 		ctx->mclk = devm_clk_get(&pdev->dev, "pmc_plt_clk_3");
+		if (IS_ERR(ctx->mclk)) {
+			ret = PTR_ERR(ctx->mclk);
+
+			dev_err(&pdev->dev,
+				"Failed to get MCLK from pmc_plt_clk_3: %d\n",
+				ret);
+			return ret;
+		}
+
 		ret = clk_prepare_enable(ctx->mclk);
 		if (ret < 0) {
 			dev_err(&pdev->dev,