aoe: get rid of cached bv variable in bufinit()

Less error prone if we just kill it, it's only used once
anyway.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/block/aoe/aoecmd.c

@@ -919,16 +919,14 @@ bio_pagedec(struct bio *bio)
 static void
 bufinit(struct buf *buf, struct request *rq, struct bio *bio)
 {
-	struct bio_vec *bv;
-
 	memset(buf, 0, sizeof(*buf));
 	buf->rq = rq;
 	buf->bio = bio;
 	buf->resid = bio->bi_size;
 	buf->sector = bio->bi_sector;
 	bio_pageinc(bio);
-	buf->bv = bv = &bio->bi_io_vec[bio->bi_idx];
-	buf->bv_resid = bv->bv_len;
+	buf->bv = &bio->bi_io_vec[bio->bi_idx];
+	buf->bv_resid = buf->bv->bv_len;
 	WARN_ON(buf->bv_resid == 0);
 }