block: get rid of MQ scheduler ops union

This is a remnant of when we had ops for both SQ and MQ
schedulers. Now it's just MQ, so get rid of the union.

Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c
index 728757a..1fd83a9 100644
--- a/block/kyber-iosched.c
+++ b/block/kyber-iosched.c
@@ -1017,7 +1017,7 @@ static const struct blk_mq_debugfs_attr kyber_hctx_debugfs_attrs[] = {
 #endif
 
 static struct elevator_type kyber_sched = {
-	.ops.mq = {
+	.ops = {
 		.init_sched = kyber_init_sched,
 		.exit_sched = kyber_exit_sched,
 		.init_hctx = kyber_init_hctx,