spi: tegra: do not use clock name to get clock

Since Tegra spi devices do not have multiple clocks, no need to use
clock name to get the clock.
Signed-off-by: NPrashant Gaikwad <pgaikwad@nvidia.com>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: NStephen Warren <swarren@nvidia.com>

drivers/spi/spi-tegra20-sflash.c

@@ -525,7 +525,7 @@ static int tegra_sflash_probe(struct platform_device *pdev)
 		goto exit_free_master;
 	}
 
-	tsd->clk = devm_clk_get(&pdev->dev, "spi");
+	tsd->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(tsd->clk)) {
 		dev_err(&pdev->dev, "can not get clock\n");
 		ret = PTR_ERR(tsd->clk);

drivers/spi/spi-tegra20-slink.c

@@ -1191,7 +1191,7 @@ static int tegra_slink_probe(struct platform_device *pdev)
 		goto exit_free_master;
 	}
 
-	tspi->clk = devm_clk_get(&pdev->dev, "slink");
+	tspi->clk = devm_clk_get(&pdev->dev, NULL);
 	if (IS_ERR(tspi->clk)) {
 		dev_err(&pdev->dev, "can not get clock\n");
 		ret = PTR_ERR(tspi->clk);