Marvell Ethernet PHYs can contain a temperature sensor, which the kernel
exports as an HWMON device. The PHY is on an MDIO bus. Add support for
this bus types to libsensors. The sensor is then displayed by sensors(1):
socaipsbus02100000ethernet02188000mdioswitch0mdio01-mdio-1
Adapter: MDIO adapter
temp1: +54.0°C (crit = +100.0°C)
Signed-off-by: Andrew Lunn <andrew@lunn.ch>