dm btree spine: remove paranoid node_check call in node_prep_for_write()

Remove this extra BUG_ON() that calls node_check() -- which avoids extra crc checking.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/persistent-data/dm-btree-spine.c

@@ -30,8 +30,6 @@ static void node_prepare_for_write(struct dm_block_validator *v,
 	h->csum = cpu_to_le32(dm_bm_checksum(&h->flags,
 					     block_size - sizeof(__le32),
 					     BTREE_CSUM_XOR));
-
-	BUG_ON(node_check(v, b, 4096));
 }
 
 static int node_check(struct dm_block_validator *v,