spi: tegra20-slink: 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>
diff --git a/drivers/spi/spi-tegra20-slink.c b/drivers/spi/spi-tegra20-slink.c
index c703536..829283e 100644
--- a/drivers/spi/spi-tegra20-slink.c
+++ b/drivers/spi/spi-tegra20-slink.c
@@ -1164,7 +1164,7 @@
 	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;
@@ -1191,7 +1191,6 @@
 	struct tegra_slink_data	*tspi = spi_master_get_devdata(master);
 
 	free_irq(tspi->irq, tspi);
-	spi_unregister_master(master);
 
 	if (tspi->tx_dma_chan)
 		tegra_slink_deinit_dma_param(tspi, false);