[SCSI] qla4xxx: Fixed active session re-open issue.

When iscsid restarted for an existing active session, set DDB will
fail with status already logged in. In this case, we have to send
logged in event to iscsid.

JIRA Key: OPENISCSI-21

Signed-off-by: Manish Rangankar <manish.rangankar@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>