Remove some (void) casts of ignored return values.

* subversion/libsvn_repos/hooks.c
  (parse_hooks_env_section, parse_hooks_env): Remove cast.

* subversion/libsvn_delta/path_driver.c
  (pop_stack): Remove cast.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1464060 13f79535-47bb-0310-9956-ffa450edef68