be2net: remove redundant D0 power state set

pci_enable_device() call sets device power state to D0; there is no need
doing it again.

Signed-off-by: Kalesh AP <kalesh.purayil@avagotech.com>
Signed-off-by: Sathya Perla <sathya.perla@avagotech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>