Remove struct net_device wrapper

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Eliminate yield() wrapper function

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Remove leftover of _{enter,exit}_pwrlock usage

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>