nvme-pci: cap queue creation to used queues

nvme-pci: cap queue creation to used queues

If the user reduces the special queue count at runtime and resets the
controller, we need to reduce the number of queues and interrupts
requested accordingly rather than start with the pre-allocated queue
count.

Tested-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>