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

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/drivers/mmc/host/mxcmmc.c b/drivers/mmc/host/mxcmmc.c
index dda0be4..776230d 100644
--- a/drivers/mmc/host/mxcmmc.c
+++ b/drivers/mmc/host/mxcmmc.c
@@ -707,7 +707,7 @@
 	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;