target: make close_session optional

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/sbp/sbp_target.c

@@ -1726,11 +1726,6 @@ static void sbp_release_cmd(struct se_cmd *se_cmd)
 	sbp_free_request(req);
 }
 
-static void sbp_close_session(struct se_session *se_sess)
-{
-	return;
-}
-
 static u32 sbp_sess_get_index(struct se_session *se_sess)
 {
 	return 0;
@@ -2344,7 +2339,6 @@ static const struct target_core_fabric_ops sbp_ops = {
 	.tpg_check_prod_mode_write_protect = sbp_check_false,
 	.tpg_get_inst_index		= sbp_tpg_get_inst_index,
 	.release_cmd			= sbp_release_cmd,
-	.close_session			= sbp_close_session,
 	.sess_get_index			= sbp_sess_get_index,
 	.write_pending			= sbp_write_pending,
 	.write_pending_status		= sbp_write_pending_status,