revert(3p/git): Revert merge of git upstream at v2.26.2

This causes cgit to serve error pages, which is undesirable.

This reverts commit 5229c9b232, reversing
changes made to f2b211131f.

third_party/git/worktree.h

@@ -44,29 +44,13 @@ int submodule_uses_worktrees(const char *path);
 const char *get_worktree_git_dir(const struct worktree *wt);
 
 /*
- * Search for the worktree identified unambiguously by `arg` -- typically
- * supplied by the user via the command-line -- which may be a pathname or some
- * shorthand uniquely identifying a worktree, thus making it convenient for the
- * user to specify a worktree with minimal typing. For instance, if the last
- * component (say, "foo") of a worktree's pathname is unique among worktrees
- * (say, "work/foo" and "work/bar"), it can be used to identify the worktree
- * unambiguously.
- *
- * `prefix` should be the `prefix` handed to top-level Git commands along with
- * `argc` and `argv`.
- *
- * Return the worktree identified by `arg`, or NULL if not found.
+ * Search a worktree that can be unambiguously identified by
+ * "arg". "prefix" must not be NULL.
  */
 struct worktree *find_worktree(struct worktree **list,
 			       const char *prefix,
 			       const char *arg);
 
-/*
- * Return the worktree corresponding to `path`, or NULL if no such worktree
- * exists.
- */
-struct worktree *find_worktree_by_path(struct worktree **, const char *path);
-
 /*
  * Return true if the given worktree is the main one.
  */