iSCSI mutex had guarded both unregister operation and destruct
operation in a single critical region in spdk_iscsi_shutdown_tgt_nodes
and spdk_iscsi_shutdown_tgt_node_by_name.
Subsequent patches will separate unregister operation and
destruct operation, and so this patch separates critical region of
unregister operation and destruct operation.
Change-Id: I847915f8277c4475c034ca64fd07ccdd47659590
Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/450583
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
da98b92b92