dm: usb: Drop the get_dev() function

This function is implemented by the legacy block functions now. Drop it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/board/cm5200/fwupdate.c b/board/cm5200/fwupdate.c
index 2ed90de..4740c83 100644
--- a/board/cm5200/fwupdate.c
+++ b/board/cm5200/fwupdate.c
@@ -105,7 +105,7 @@
 
 	/* Detect storage device */
 	for (devno = 0; devno < USB_MAX_STOR_DEV; devno++) {
-		stor_dev = usb_stor_get_dev(devno);
+		stor_dev = blk_get_devnum_by_type(IF_TYPE_USB, devno);
 		if (stor_dev->type != DEV_TYPE_UNKNOWN)
 			break;
 	}