net: fman_memac: use pcs-lynx's check for fwnode availability

Use pcs-lynx's check rather than our own when determining if the device
is available. This fixes a bug where the reference gained by
of_parse_phandle() is not dropped if the device is not available.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/freescale/fman/fman_memac.c

@@ -1042,7 +1042,7 @@ static struct phylink_pcs *memac_pcs_create(struct device_node *mac_node,
 	struct phylink_pcs *pcs;
 
 	node = of_parse_phandle(mac_node, "pcsphy-handle", index);
-	if (!node || !of_device_is_available(node))
+	if (!node)
 		return ERR_PTR(-ENODEV);
 
 	pcs = lynx_pcs_create_fwnode(of_fwnode_handle(node));