block: remove the nr_sectors variable in generic_make_request_checks

The variable is only used once, so just open code the bio_sector()
there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-core.c

@@ -974,7 +974,6 @@ static noinline_for_stack bool
 generic_make_request_checks(struct bio *bio)
 {
 	struct request_queue *q = bio->bi_disk->queue;
-	int nr_sectors = bio_sectors(bio);
 	blk_status_t status = BLK_STS_IOERR;
 
 	might_sleep();
@@ -1007,7 +1006,7 @@ generic_make_request_checks(struct bio *bio)
 	if (op_is_flush(bio->bi_opf) &&
 	    !test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
 		bio->bi_opf &= ~(REQ_PREFLUSH | REQ_FUA);
-		if (!nr_sectors) {
+		if (!bio_sectors(bio)) {
 			status = BLK_STS_OK;
 			goto end_io;
 		}