iscsi-target: call complete on conn_logout_comp

ISCSI_HW_OFFLOAD transport drivers waits
on conn_logout_comp as ISCSI_TCP driver
so call complete if transport type
is ISCSI_HW_OFFLOAD.

Signed-off-by: Varun Prakash <varun@chelsio.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>