linux-phytec-fsl

MLK-14438-06 net: fec: add property to define exclusive MII bus

In defalut, most of i.MX boards share one MII bus in boards design to reduce
pins utilize, but others each MAC use their exclusive MII bus. To solve the
problem, user can select to define the mii-exclusive property in board dts file.

The patch also update binding doc.

Signed-off-by: Fugang Duan <fugang.duan@nxp.com>