FROMGIT: block/mq-deadline: Rename dd_init_queue() and dd_exit_queue()

Change "queue" into "sched" to make the function names reflect better the
purpose of these functions.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
BUG: 187357408
Change-Id: I30825b379146dbaef4ff3f85148b2e788667a77c
(cherry picked from commit a6e57fe5ab09c250fc741294e6321270a4364fec git://git.kernel.dk/linux-block/

 for-5.14/block)
Signed-off-by: Bart Van Assche <bvanassche@google.com>