NVMe: Update module version major number

It's already near impossible to tell what bits someone is running based on
a 'modinfo nvme', and I don't want to try guessing if someone is running
blk-mq or bio-based. Let's make it obvious with the module version that
the blk-mq conversion is a major change. Future bio-based versions can
increment to 0.10 in a fork if revisions occur.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>