netdev/fec.c: add phylib supporting to enable carrier detection

BugLink: http://bugs.launchpad.net/bugs/457878

 - removed old MII phy control code
 - add phylib supporting
 - add ethtool interface to make user space NetworkManager works

This patch is ready for upstream, it will be pushed to upstream for merge

Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Acked-by: Amit Kucheria <amit.kucheria@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>