staging: et131x: Remove adapter->bmsr, replace with phydev equivalents

adapter->bmsr is no longer being updated, but is also used to check the link state in places.

Remove bmsr from adapter, and replace link state checks with phydev->link check.

Signed-off-by: Mark Einon <mark.einon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>