[PATCH] forcedeth: mac address corrected

This patch will correct the mac address and set a flag to indicate that
it is already corrected in case nv_probe is called again. For example,
when you use kexec to restart the kernel.

Signed-Off-By: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>