[PATCH] sis190: make 10Mbps the default when handling the StationControl register

[PATCH] sis190: make 10Mbps the default when handling the StationControl register

This patch does three things:
- widen the access to the StationControl register (note the SIS_W16
  versus SIS_W32 change);
- default to 10Mbps half duplex when the LPA can not be evaluated
  (reg31->ctl is identical for both). It can be argued that it makes
  sense as the lowest common denominator when everything else failed.
  Btw it works better than the current code. :o)
- remove some enums: they do not document anymore.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>