Merge branch 'ma/worktree-cleanups'

Code clean-up.

* ma/worktree-cleanups:
  worktree: use skip_prefix to parse target
  worktree: rename copy-pasted variable
  worktree: update renamed variable in comment
  worktree: inline `worktree_ref()` into its only caller
  wt-status: introduce wt_status_state_free_buffers()
  wt-status: print to s->fp, not stdout
  wt-status: replace sha1 mentions with oid

ref-filter.c

@@ -1557,9 +1557,7 @@ char *get_head_description(void)
 		strbuf_addstr(&desc, _("no branch"));
 	strbuf_addch(&desc, ')');
 
-	free(state.branch);
-	free(state.onto);
-	free(state.detached_from);
+	wt_status_state_free_buffers(&state);
 	return strbuf_detach(&desc, NULL);
 }