The extended device socket cannot turn on/off while system is running.
So when system boots up and the device is not power on, the fjes driver
does not need be loaded.

To check the status of the device, the patch adds ACPI _STA method check.
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
CC: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>