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-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index c665d1d..f8ac50c 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -39,7 +39,7 @@
 #define NVQUIRK_ENABLE_SDHCI_SPEC_300	BIT(2)
 
 struct sdhci_tegra_soc_data {
-	struct sdhci_pltfm_data *pdata;
+	const struct sdhci_pltfm_data *pdata;
 	u32 nvquirks;
 };
 
@@ -156,7 +156,7 @@
 	.platform_reset_exit = tegra_sdhci_reset_exit,
 };
 
-static struct sdhci_pltfm_data sdhci_tegra20_pdata = {
+static const struct sdhci_pltfm_data sdhci_tegra20_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
 		  SDHCI_QUIRK_NO_HISPD_BIT |
@@ -170,7 +170,7 @@
 		    NVQUIRK_ENABLE_BLOCK_GAP_DET,
 };
 
-static struct sdhci_pltfm_data sdhci_tegra30_pdata = {
+static const struct sdhci_pltfm_data sdhci_tegra30_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
@@ -184,7 +184,7 @@
 	.nvquirks = NVQUIRK_ENABLE_SDHCI_SPEC_300,
 };
 
-static struct sdhci_pltfm_data sdhci_tegra114_pdata = {
+static const struct sdhci_pltfm_data sdhci_tegra114_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 		  SDHCI_QUIRK_SINGLE_POWER_WRITE |