mfd: fix tmio related warnings

We can not have .driver_data as const since platform_set_drvdata() doesnt take
a const.
The hclk mmc_data field can be const though.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/tc6387xb.c

@@ -75,7 +75,7 @@ static int tc6387xb_mmc_disable(struct platform_device *mmc)
 
 /*--------------------------------------------------------------------------*/
 
-const static struct tmio_mmc_data tc6387xb_mmc_data = {
+static struct tmio_mmc_data tc6387xb_mmc_data = {
 	.hclk = 24000000,
 };