target: Only reset specific dynamic entries during lun_group creation

This patch changes core_tpg_add_node_to_devs() to avoid unnecessarly
resetting every se_dev_entry in se_node_acl->tpg_lun_hlist when the
operation is driven by an explicit configfs se_lun->lun_group creation
via core_dev_add_lun() to only update a single se_lun.

Otherwise for the second core_tpg_check_initiator_node_acl() case, go
ahead and continue to scan the full set of currently active se_lun in
se_portal_group->tpg_lun_hlist.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
diff --git a/drivers/target/target_core_internal.h b/drivers/target/target_core_internal.h
index 2c160ce..ce80ca7 100644
--- a/drivers/target/target_core_internal.h
+++ b/drivers/target/target_core_internal.h
@@ -64,7 +64,8 @@
 
 struct se_node_acl *__core_tpg_get_initiator_node_acl(struct se_portal_group *tpg,
 		const char *);
-void	core_tpg_add_node_to_devs(struct se_node_acl *, struct se_portal_group *);
+void	core_tpg_add_node_to_devs(struct se_node_acl *, struct se_portal_group *,
+				  struct se_lun *);
 void	core_tpg_wait_for_nacl_pr_ref(struct se_node_acl *);
 struct se_lun *core_tpg_alloc_lun(struct se_portal_group *, u32);
 int	core_tpg_add_lun(struct se_portal_group *, struct se_lun *,