block: Remove obsolete configs BLK_MQ_{PCI,VIRTIO}

Commit 9bc1e897 ("blk-mq: remove unused queue mapping helpers") makes
the two config options, BLK_MQ_PCI and BLK_MQ_VIRTIO, have no remaining
effect.

Remove the two obsolete config options.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@redhat.com>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20250514065513.463941-1-lukas.bulwahn@redhat.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>