scsi: qla2xxx: Restore FAWWPN of Physical Port only for loop down

When loop was made down explicitly due to cable pull, then for N2N toplogy,
if FAWWPN BIT is enabled by user, then it would restore some default
(garbage) value for Physical port WWPN, so this show garbage WWPN for the
port. Fix is, to restore physical port WWPN, if it is fabric
configuration. When loop is explicitly made down, and FAWWPN feature is
enabled, then driver need to restore original flashed WWPN.

Signed-off-by: Sawan Chandak <schandak@marvell.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>