block: use memcpy_from_bvec in bio_copy_kern_endio_read

Use memcpy_from_bvec instead of open coding the logic.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210727055646.118787-13-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-map.c

@@ -400,7 +400,7 @@ static void bio_copy_kern_endio_read(struct bio *bio)
 	struct bvec_iter_all iter_all;
 
 	bio_for_each_segment_all(bvec, bio, iter_all) {
-		memcpy(p, page_address(bvec->bv_page), bvec->bv_len);
+		memcpy_from_bvec(p, bvec);
 		p += bvec->bv_len;
 	}