bcachefs: Reduce max nr of btree iters when lockdep is on

This is so we don't overflow MAX_LOCK_DEPTH.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_types.h

@@ -275,7 +275,11 @@ struct btree_insert_entry {
 	struct btree_iter	*iter;
 };
 
+#ifndef CONFIG_LOCKDEP
 #define BTREE_ITER_MAX		64
+#else
+#define BTREE_ITER_MAX		32
+#endif
 
 struct btree_trans {
 	struct bch_fs		*c;