dm: add missing trace_block_split() to __split_and_process_bio()

commit 075c18c3e124a1511ebc10a89f1858c8a77dcb01 upstream.

Provides useful context about bio splits in blktrace.
Signed-off-by: NMike Snitzer <snitzer@redhat.com>
Signed-off-by: NJoseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: NShile Zhang <shile.zhang@linux.alibaba.com>
Acked-by: NCaspar Zhang <caspar@linux.alibaba.com>

drivers/md/dm.c

@@ -1629,6 +1629,7 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md,
 				part_stat_unlock();
 
 				bio_chain(b, bio);
+				trace_block_split(md->queue, b, bio->bi_iter.bi_sector);
 				ret = generic_make_request(bio);
 				break;
 			}