f2fs: drop bio->bi_rw manual assignment

Merge 4fc29c1aa375 included this extra line, but it's not needed (or
useful) since we'll bio_set_op_attrs() right after to properly set
the op and flags for the bio.

Signed-off-by: Jens Axboe <axboe@fb.com>

fs/f2fs/data.c

@@ -245,7 +245,6 @@ int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 		bio_put(bio);
 		return -EFAULT;
 	}
-	bio->bi_rw = fio->op_flags;
 	bio_set_op_attrs(bio, fio->op, fio->op_flags);
 
 	__submit_bio(fio->sbi, bio, fio->type);