[SCSI] dpt_i2o: convert to SCSI hotplug model

 - Delete refereces to HOSTS_C
 - Switch to module_init/module_exit instead of detect/release
 - Don't pass around the host template and rename it to adpt_template
 - Switch from scsi_register/scsi_unregister to scsi_host_alloc,
   scsi_add_host, scsi_scan_host and scsi_host_put.

Signed-off-by: Matthew Wilcox <matthew@wil.cx>
Acked-by: "Salyzyn, Mark" <mark_salyzyn@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>