bcachefs: btree_path_make_mut() clears should_be_locked

This fixes a bug where __bch2_btree_node_update_key() wasn't clearing
should_be_locked, leading to bch2_btree_path_traverse() always failing -
all callers of btree_path_make_mut() want should_be_locked cleared, so
do it there.
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>

fs/bcachefs/btree_iter.c

@@ -1662,9 +1662,8 @@ static struct btree_path *btree_path_clone(struct btree_trans *trans, struct btr
 	return new;
 }
 
-struct btree_path * __must_check
-__bch2_btree_path_make_mut(struct btree_trans *trans,
-			   struct btree_path *path, bool intent)
+struct btree_path *__bch2_btree_path_make_mut(struct btree_trans *trans,
+			 struct btree_path *path, bool intent)
 {
 	__btree_path_put(path, intent);
 	path = btree_path_clone(trans, path, intent);
@@ -1672,6 +1671,7 @@ __bch2_btree_path_make_mut(struct btree_trans *trans,
 #ifdef CONFIG_BCACHEFS_DEBUG
 	path->ip_allocated = _RET_IP_;
 #endif
+	path->should_be_locked = false;
 	return path;
 }
 
@@ -1688,7 +1688,6 @@ __bch2_btree_path_set_pos(struct btree_trans *trans,
 	path = bch2_btree_path_make_mut(trans, path, intent);
 
 	path->pos		= new_pos;
-	path->should_be_locked	= false;
 	trans->paths_sorted	= false;
 
 	if (unlikely(path->cached)) {

fs/bcachefs/btree_iter.h

@@ -149,6 +149,7 @@ bch2_btree_path_make_mut(struct btree_trans *trans,
 {
 	if (path->ref > 1 || path->preserve)
 		path = __bch2_btree_path_make_mut(trans, path, intent);
+	path->should_be_locked = false;
 	return path;
 }