mxcmmc: Do not pass clock name, we have only one clock for this device

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

drivers/mmc/host/mxcmmc.c

@@ -707,7 +707,7 @@ static int mxcmci_probe(struct platform_device *pdev)
 	host->res = r;
 	host->irq = irq;
 
-	host->clk = clk_get(&pdev->dev, "sdhc_clk");
+	host->clk = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(host->clk)) {
 		ret = PTR_ERR(host->clk);
 		goto out_iounmap;