[SCSI] iscsi: support mutiple daemons

Patch from david.somayajulu@qlogic.com and cleaned up by Tomo.

qla4xxx is going to have a different daemon so this patch
just routes the events to the right daemon.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>