nvmet: add tracing of zns commands

Add nvme_cmd_zone_append, nvme_cmd_zone_mgmt_send and
nvme_cmd_zone_mgmt_recv parse to nvme target tracing.

Signed-off-by: Guixin Liu <kanie@linux.alibaba.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Keith Busch <kbusch@kernel.org>