mmc: sdhci_pltfm: Constify sdhci_pltfm_data

The sdhci_pltfm_data struct is never modified within the sdhci_pltfm
module. So make the pdata parameter to sdhci_pltfm_init and
sdhci_pltfm_register const.  This allows drivers to declare their
sdhci_pltfm_data struct as const.

This patch also makes the sdhci_pltfm_data declarations const where
possible.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
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 153b6c5..a3bfc1e 100644
--- a/drivers/mmc/host/sdhci-pltfm.h
+++ b/drivers/mmc/host/sdhci-pltfm.h
@@ -91,11 +91,11 @@
 extern void sdhci_get_of_property(struct platform_device *pdev);
 
 extern struct sdhci_host *sdhci_pltfm_init(struct platform_device *pdev,
-					   struct sdhci_pltfm_data *pdata);
+					  const struct sdhci_pltfm_data *pdata);
 extern void sdhci_pltfm_free(struct platform_device *pdev);
 
 extern int sdhci_pltfm_register(struct platform_device *pdev,
-				struct sdhci_pltfm_data *pdata);
+				const struct sdhci_pltfm_data *pdata);
 extern int sdhci_pltfm_unregister(struct platform_device *pdev);
 
 extern unsigned int sdhci_pltfm_clk_get_max_clock(struct sdhci_host *host);