Improve code uniformity.  No functional change.

* subversion/libsvn_subr/file.c
  (reclaim_shared_handle,
   close_handle): use our wrapper macro instead of calling APR directly

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1533814 13f79535-47bb-0310-9956-ffa450edef68