net: ethernet: ax88796: make mdiobb_ops const

Make this const as it is only stored in a const field of a
mdiobb_ctrl structure.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/8390/ax88796.c

@@ -585,7 +585,7 @@ static int ax_bb_get_data(struct mdiobb_ctrl *ctrl)
 	return reg_memr & AX_MEMR_MDI ? 1 : 0;
 }
 
-static struct mdiobb_ops bb_ops = {
+static const struct mdiobb_ops bb_ops = {
 	.owner = THIS_MODULE,
 	.set_mdc = ax_bb_mdc,
 	.set_mdio_dir = ax_bb_dir,