fs/bio.c: fix shadows sparse warning

fs/bio.c:81:33: warning: symbol 'bslab' shadows an earlier one
fs/bio.c:74:25: originally declared here
Signed-off-by: NThiago Farina <tfransosi@gmail.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

fs/bio.c

@@ -78,7 +78,7 @@ static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size)
 
 	i = 0;
 	while (i < bio_slab_nr) {
-		struct bio_slab *bslab = &bio_slabs[i];
+		bslab = &bio_slabs[i];
 
 		if (!bslab->slab && entry == -1)
 			entry = i;