net: add ColdFire support to the smc91x driver

Some embedded ColdFire based boards use the SMC 91x family of ethernet
devices. (For example the Freescale M5249C3 and MoretonBay NETtel).

Add IO access support to the SMC91x driver, and allow this driver to
be configured for ColdFire platforms.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: David S. Miller <davem@davemloft.net>