[POWERPC] MPC8349E-mITX: Vitesse 7385 PHY is not connected to the MDIO bus

...thus use fixed-link to register proper "Fixed PHY"

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Vitaly Bordug <vitb@kernel.crashing.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>