nvme: add tracepoint for nvme_setup_cmd

nvme: add tracepoint for nvme_setup_cmd

Add tracepoints for nvme_setup_cmd() for tracing admin and/or nvm commands.

Examples of the two tracepoints are as follows for trace_nvme_setup_admin_cmd():
kworker/u8:0-5     [003] ....     2.998792: nvme_setup_admin_cmd: cmdid=14, flags=0x0, meta=0x0, cmd=(nvme_admin_create_cq cqid=1, qsize=1023, cq_flags=0x3, irq_vector=0)

and trace_nvme_setup_nvm_cmd():
dd-205   [001] ....     3.503929: nvme_setup_nvm_cmd: qid=1, nsid=1, cmdid=989, flags=0x0, meta=0x0, cmd=(nvme_cmd_read slba=4096, len=2047, ctrl=0x0, dsmgmt=0, reftag=0)

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>