vim-patch:8.0.1496: VIM_CLEAR()

Problem:    Clearing a pointer takes two lines.
Solution:   Add VIM_CLEAR() and replace vim_clear(). (Hirohito Higashi,
            closes #2629)

vim-patch:8.0.1481

src/nvim/search.c

@@ -4290,8 +4290,7 @@ find_pattern_in_path(
                 prev_fname = NULL;
               }
             }
-            xfree(new_fname);
-            new_fname = NULL;
+            XFREE_CLEAR(new_fname);
             already_searched = TRUE;
             break;
           }