dm: mmc: Update mmc_get_mmc_dev() to use const *

This function does not modify the device to change it to use const *, so
that callers with a const udevice * can call it without a cast.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NJaehoon Chung <jh80.chung@samsung.com>

drivers/mmc/mmc-uclass.c

@@ -239,7 +239,7 @@ int mmc_of_parse(struct udevice *dev, struct mmc_config *cfg)
 	return 0;
 }
 
-struct mmc *mmc_get_mmc_dev(struct udevice *dev)
+struct mmc *mmc_get_mmc_dev(const struct udevice *dev)
 {
 	struct mmc_uclass_priv *upriv;
 

include/mmc.h

@@ -377,7 +377,7 @@ struct mmc_uclass_priv {
  * @dev:	Device
  * @return associated mmc struct pointer if available, else NULL
  */
-struct mmc *mmc_get_mmc_dev(struct udevice *dev);
+struct mmc *mmc_get_mmc_dev(const struct udevice *dev);
 
 /* End of driver model support */