nvme: use blk_mq_start_hw_queues() in nvme_kill_queues()

nvme: use blk_mq_start_hw_queues() in nvme_kill_queues()

commit 806f026f9b901eaf1a6baeb48b5da18d6a4f818e upstream.

Inside nvme_kill_queues(), we have to start hw queues for
draining requests in sw queues, .dispatch list and requeue list,
so use blk_mq_start_hw_queues() instead of blk_mq_start_stopped_hw_queues()
which only run queues if queues are stopped, but the queues may have
been started already, for example nvme_start_queues() is called in reset work
function.

blk_mq_start_hw_queues() run hw queues in current context, instead
of running asynchronously like before. Given nvme_kill_queues() is
run from either remove context or reset worker context, both are fine
to run hw queue directly. And the mutex of namespaces_mutex isn't a
problem too becasue nvme_start_freeze() runs hw queue in this way
already.

Reported-by: Zhang Yi <yizhan@redhat.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>