nvme: add get-feature to admin cmds tracer

This will print get-feature cmd in more informative way. For example,
run "nvme get-feature /dev/nvme0 -n 1 -f 0x9 -c 10" will trace:

 nvme-3907  [008] ....  1763.635054: nvme_setup_cmd: nvme0: qid=0, cmdid=6, nsid=1, flags=0x0, meta=0x0, cmd=(nvme_admin_get_features fid=0x9 sel=0x0 cdw11=0xa)
<idle>-0     [001] d.h.  1763.635112: nvme_sq: nvme0: qid=0, head=27, tail=27
<idle>-0     [008] ..s.  1763.635121: nvme_complete_rq: nvme0: qid=0, cmdid=6, res=10, retries=0, flags=0x2, status=0

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>