mmc: block: set GENHD_FL_NVMEM

Set flag to consider MMC block devices as NVMEM providers.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

drivers/mmc/core/block.c

@@ -2467,6 +2467,7 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
 	md->disk->major	= MMC_BLOCK_MAJOR;
 	md->disk->minors = perdev_minors;
 	md->disk->first_minor = devidx * perdev_minors;
+	md->disk->flags = GENHD_FL_NVMEM;
 	md->disk->fops = &mmc_bdops;
 	md->disk->private_data = md;
 	md->parent = parent;