Coldfire: mcfmii: Allow non-autonegotiating PHYs to use mii command

Modified mii_init to support boards with PHYs that are not set to
autonegotiate, but still want to use u-boot's mii commands to probe
the smi bus. Such PHYs will not set the Autonegotiate-done bit.

Signed-off-by: Richard Retanubun <RichardRetanubun@RuggedCom.com>