revert "drivers/net/tulip/dmfe: support basic carrier detection"

Revert 7628b0a8.  Thomas Bachler
reports:

  Commit 7628b0a8 (drivers/net/tulip/dmfe:
  support basic carrier detection) breaks networking on my Davicom DM9009.
  ethtool always reports there is no link.  tcpdump shows incoming packets,
  but TX is disabled.  Reverting the above patch fixes the problem.

Cc: Samuel Thibault <samuel.thibault@ens-lyon.org>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Valerie Henson <val_henson@linux.intel.com>
Cc: Thomas Bachler <thomas@archlinux.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>