nvme: move the call to nvme_init_identify earlier

We want to record the identify and CAP values even if no I/O queue
is available.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>