net: ks8851: Select PHYLIB and MICREL_PHY in Kconfig

The PHYLIB must be selected to provide mdiobus_*() functions, and the
MICREL_PHY is necessary too, as that is the only possible PHY attached
to the KS8851 (it is the internal PHY).

Fixes: ef3631220d ("net: ks8851: Register MDIO bus and the internal PHY")
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: Lukas Wunner <lukas@wunner.de>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20210111125046.36326-1-marex@denx.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/micrel/Kconfig

@@ -31,6 +31,8 @@ config KS8851
 	select MII
 	select CRC32
 	select EEPROM_93CX6
+	select PHYLIB
+	select MICREL_PHY
 	help
 	  SPI driver for Micrel KS8851 SPI attached network chip.
 
@@ -40,6 +42,8 @@ config KS8851_MLL
 	select MII
 	select CRC32
 	select EEPROM_93CX6
+	select PHYLIB
+	select MICREL_PHY
 	help
 	  This platform driver is for Micrel KS8851 Address/data bus
 	  multiplexed network chip.