mmc: sdhci-esdhc: use writel/readl as general APIs

Add one flag to indicate the GPIO CD/WP is enabled or not
on imx platforms, and reuse the writel/readl as the general
APIs for imx SOCs.

Signed-off-by: Richard Zhu <Hong-Xing.Zhu@freescale.com>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/host/sdhci-pltfm.h b/drivers/mmc/host/sdhci-pltfm.h
index ea2e44d..2b37016 100644
--- a/drivers/mmc/host/sdhci-pltfm.h
+++ b/drivers/mmc/host/sdhci-pltfm.h
@@ -17,7 +17,7 @@
 
 struct sdhci_pltfm_host {
 	struct clk *clk;
-	u32 scratchpad; /* to handle quirks across io-accessor calls */
+	void *priv; /* to handle quirks across io-accessor calls */
 };
 
 extern struct sdhci_pltfm_data sdhci_cns3xxx_pdata;