net: phy: fix mdio-mscc-miim build

PHYLIB is not selected by mdio-mscc-miim but it uses mdio devres helpers.
Explicitly select MDIO_DEVRES in this driver's Kconfig entry.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: 1814cff2

 ("net: phy: add a Kconfig option for mdio_devres")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>