bcachefs: kill trans_for_each_path_from()

dead code
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/btree_iter.h

@@ -74,14 +74,11 @@ __trans_next_path(struct btree_trans *trans, unsigned idx)
 	return &trans->paths[idx];
 }
 
-#define trans_for_each_path_from(_trans, _path, _start)			\
-	for (_path = __trans_next_path((_trans), _start);		\
+#define trans_for_each_path(_trans, _path)				\
+	for (_path = __trans_next_path((_trans), 1);			\
 	     (_path);							\
 	     _path = __trans_next_path((_trans), (_path)->idx + 1))
 
-#define trans_for_each_path(_trans, _path)				\
-	trans_for_each_path_from(_trans, _path, 1)
-
 static inline struct btree_path *
 __trans_next_path_safe(struct btree_trans *trans, unsigned *idx)
 {