spi: tegra20-sflash: use devm_spi_register_master()

Use devm_spi_register_master() to make cleanup paths simpler.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/spi/spi-tegra20-sflash.c

@@ -529,7 +529,7 @@ static int tegra_sflash_probe(struct platform_device *pdev)
 	pm_runtime_put(&pdev->dev);
 
 	master->dev.of_node = pdev->dev.of_node;
-	ret = spi_register_master(master);
+	ret = devm_spi_register_master(&pdev->dev, master);
 	if (ret < 0) {
 		dev_err(&pdev->dev, "can not register to master err %d\n", ret);
 		goto exit_pm_disable;
@@ -553,7 +553,6 @@ static int tegra_sflash_remove(struct platform_device *pdev)
 	struct tegra_sflash_data	*tsd = spi_master_get_devdata(master);
 
 	free_irq(tsd->irq, tsd);
-	spi_unregister_master(master);
 
 	pm_runtime_disable(&pdev->dev);
 	if (!pm_runtime_status_suspended(&pdev->dev))