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.c b/common/cmd_usb.c
index a540b42..c7b642c 100644
--- a/common/cmd_usb.c
+++ b/common/cmd_usb.c
@@ -759,7 +759,7 @@
 			printf("\nUSB read: device %d block # %ld, count %ld"
 				" ... ", usb_stor_curr_dev, blk, cnt);
 			stor_dev = usb_stor_get_dev(usb_stor_curr_dev);
-			n = stor_dev->block_read(usb_stor_curr_dev, blk, cnt,
+			n = stor_dev->block_read(stor_dev, blk, cnt,
 						 (ulong *)addr);
 			printf("%ld blocks read: %s\n", n,
 				(n == cnt) ? "OK" : "ERROR");
@@ -781,7 +781,7 @@
 			printf("\nUSB write: device %d block # %ld, count %ld"
 				" ... ", usb_stor_curr_dev, blk, cnt);
 			stor_dev = usb_stor_get_dev(usb_stor_curr_dev);
-			n = stor_dev->block_write(usb_stor_curr_dev, blk, cnt,
+			n = stor_dev->block_write(stor_dev, blk, cnt,
 						(ulong *)addr);
 			printf("%ld blocks write: %s\n", n,
 				(n == cnt) ? "OK" : "ERROR");