[SCSI] bnx2i: register given device with cnic if shost != NULL in ep_connect()

When using iface, bnx2i was unable to offload further connections after all
active sessions are logged out. bnx2i will unregister the device from cnic
when the last connection is torn down. Next call to ep_connect() will fail
because the device is not registered. This issue is not seen if shost == NULL
is passed to ep_connect() call because in that case bnx2i will registers all
known devices with cnic before doing a route look-up.  When shost != NULL,
bnx2i knows the device on which to offload the connection and has to register
this device before attempting to offload the connection

Signed-off-by: Anil Veerabhadrappa <anilgv@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Reviewed-by Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>