dm: Drop the block_dev_desc_t typedef

Use 'struct' instead of a typdef. Also since 'struct block_dev_desc' is long
and causes 80-column violations, rename it to struct blk_desc.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Stephen Warren <swarren@nvidia.com>
diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index ede5d6e..b19b328 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -234,7 +234,7 @@
 	return blkcnt;
 }
 
-static ulong mmc_bread(block_dev_desc_t *block_dev, lbaint_t start,
+static ulong mmc_bread(struct blk_desc *block_dev, lbaint_t start,
 		       lbaint_t blkcnt, void *dst)
 {
 	int dev_num = block_dev->dev;
@@ -1579,7 +1579,7 @@
 }
 
 #ifdef CONFIG_PARTITIONS
-block_dev_desc_t *mmc_get_dev(int dev)
+struct blk_desc *mmc_get_dev(int dev)
 {
 	struct mmc *mmc = find_mmc_device(dev);
 	if (!mmc || mmc_init(mmc))