scsi: libfc: Do not drop down to FLOGI for fc_rport_login()

When fc_rport_login() is called while the rport is not
in RPORT_ST_INIT, RPORT_ST_READY, or RPORT_ST_DELETE
login is already in progress and there's no need to
drop down to FLOGI; doing so will only confuse the
other side.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Acked-by: Johannes Thumshirn <jth@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>