When the ethaddr is changed in the env, update the device pdata at the
same time (only if it is probed for the DM case; only if registered for
the non-DM case). Again this gets us closer to completely non-polled
env needed to simplify the net_loop.
This requires that the NET feature select the REGEX feature.
Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>