ARM: dts: vf610-zii-dev: use XAUI for DSA link ports

Use XAUI rather than XGMII for DSA link ports, as this is the interface
mode that the switches actually use. XAUI is the 4 lane bus with clock
per direction, whereas XGMII is a 32 bit bus with clock.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>