ASoC: ti: omap-mcbsp: Fix an error handling path in 'asoc_mcbsp_probe()'

If an error occurs after the call to 'omap_mcbsp_init()', the reference to
'mcbsp->fclk' must be decremented, as already done in the remove function.

This can be achieved easily by using the devm_ variant of 'clk_get()'
when the reference is taken in 'omap_mcbsp_init()'

This fixes the leak in the probe and has the side effect to simplify both
the error handling path of 'omap_mcbsp_init()' and the remove function.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Peter Ujfalusi <peter.ujflausi@ti.com>
Link: https://lore.kernel.org/r/20200512134325.252073-1-christophe.jaillet@wanadoo.frSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/ti/omap-mcbsp.c

@@ -686,7 +686,7 @@ static int omap_mcbsp_init(struct platform_device *pdev)
 	mcbsp->dma_data[1].addr = omap_mcbsp_dma_reg_params(mcbsp,
 						SNDRV_PCM_STREAM_CAPTURE);
 
-	mcbsp->fclk = clk_get(&pdev->dev, "fck");
+	mcbsp->fclk = devm_clk_get(&pdev->dev, "fck");
 	if (IS_ERR(mcbsp->fclk)) {
 		ret = PTR_ERR(mcbsp->fclk);
 		dev_err(mcbsp->dev, "unable to get fck: %d\n", ret);
@@ -711,7 +711,7 @@ static int omap_mcbsp_init(struct platform_device *pdev)
 		if (ret) {
 			dev_err(mcbsp->dev,
 				"Unable to create additional controls\n");
-			goto err_thres;
+			return ret;
 		}
 	}
 
@@ -724,8 +724,6 @@ static int omap_mcbsp_init(struct platform_device *pdev)
 err_st:
 	if (mcbsp->pdata->buffer_size)
 		sysfs_remove_group(&mcbsp->dev->kobj, &additional_attr_group);
-err_thres:
-	clk_put(mcbsp->fclk);
 	return ret;
 }
 
@@ -1442,8 +1440,6 @@ static int asoc_mcbsp_remove(struct platform_device *pdev)
 
 	omap_mcbsp_st_cleanup(pdev);
 
-	clk_put(mcbsp->fclk);
-
 	return 0;
 }