block: pass block dev not num to read/write/erase()

This will allow the implementation to make use of data in the block_dev
structure beyond the base device number. This will be useful so that eMMC
block devices can encompass the HW partition ID rather than treating this
out-of-band. Equally, the existence of the priv field is crying out for
this patch to exist.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/common/cmd_usb_mass_storage.c b/common/cmd_usb_mass_storage.c
index 0407389..f4bafec 100644
--- a/common/cmd_usb_mass_storage.c
+++ b/common/cmd_usb_mass_storage.c
@@ -19,9 +19,8 @@
 {
 	block_dev_desc_t *block_dev = ums_dev->block_dev;
 	lbaint_t blkstart = start + ums_dev->start_sector;
-	int dev_num = block_dev->dev;
 
-	return block_dev->block_read(dev_num, blkstart, blkcnt, buf);
+	return block_dev->block_read(block_dev, blkstart, blkcnt, buf);
 }
 
 static int ums_write_sector(struct ums *ums_dev,
@@ -29,9 +28,8 @@
 {
 	block_dev_desc_t *block_dev = ums_dev->block_dev;
 	lbaint_t blkstart = start + ums_dev->start_sector;
-	int dev_num = block_dev->dev;
 
-	return block_dev->block_write(dev_num, blkstart, blkcnt, buf);
+	return block_dev->block_write(block_dev, blkstart, blkcnt, buf);
 }
 
 static struct ums ums_dev = {