mmc: sdhci-spear: Initialize sdhci clk to 50 MHz

SPEAr sdhci driver expects the clock to be set to 50 MHz for proper
functioning.  This patch sets clk to 50 MHz in probe.
Signed-off-by: NVipul Kumar Samar <vipulkumar.samar@st.com>
Signed-off-by: NViresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: NChris Ball <cjb@laptop.org>

drivers/mmc/host/sdhci-spear.c

@@ -146,6 +146,11 @@ static int __devinit sdhci_probe(struct platform_device *pdev)
 		goto put_clk;
 	}
 
+	ret = clk_set_rate(sdhci->clk, 50000000);
+	if (ret)
+		dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n",
+				clk_get_rate(sdhci->clk));
+
 	if (np) {
 		sdhci->data = sdhci_probe_config_dt(pdev);
 		if (IS_ERR(sdhci->data)) {