arm: mvebu: a38x: Switch back to mdio_alloc()

Use mdio_alloc() again to allocate MDIO bus. This is possible
because all the miiphybb parameters and ops passing is handled in
at bb_miiphy_read()/bb_miiphy_write() level.

Signed-off-by: Marek Vasut <marek.vasut+renesas@mailbox.org>
Reviewed-by: Paul Barker <paul.barker.ct@bp.renesas.com>
diff --git a/board/gdsys/a38x/ihs_phys.c b/board/gdsys/a38x/ihs_phys.c
index 7aa427e..d513018 100644
--- a/board/gdsys/a38x/ihs_phys.c
+++ b/board/gdsys/a38x/ihs_phys.c
@@ -244,14 +244,9 @@
 
 int register_miiphy_bus(uint k, struct mii_dev **bus)
 {
-	struct bb_miiphy_bus *bb_miiphy = bb_miiphy_alloc();
-	struct mii_dev *mdiodev;
+	struct mii_dev *mdiodev = mdio_alloc();
 	int retval;
 
-	if (!bb_miiphy)
-		return -ENOMEM;
-
-	mdiodev = &bb_miiphy->mii;
 	snprintf(mdiodev->name, MDIO_NAME_LEN, "ihs%d", k);
 	mdiodev->read = mii_bb_miiphy_read;
 	mdiodev->write = mii_bb_miiphy_write;
@@ -260,7 +255,7 @@
 	retval = mdio_register(mdiodev);
 	if (retval < 0)
 		return retval;
-	*bus = &bb_miiphy->mii;
+	*bus = mdiodev;
 
 	return mii_mdio_init(k);
 }