net: stmmac: mdio: use netdev_priv() directly

net: stmmac: mdio: use netdev_priv() directly

netdev_priv() is an inline function, taking a struct net_device
pointer. When passing in the MII bus->priv, which is a void pointer,
there is no need to go via a local ndev variable to type it first.

Thus, instead of:

	struct net_device *ndev = bus->priv;
	struct stmmac_priv *priv;
...
	priv = netdev_priv(ndev);

we can simply do:

	struct stmmac_priv *priv = netdev_priv(bus->priv);

which simplifies the code.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Subbaraya Sundeep <sbhatta@marvell.com>
Link: https://patch.msgid.link/E1urBj2-000000002as-0pod@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>