As per convention, iteration pools shall be named "iterpool".

* subversion/libsvn_fs_fs/index.c
  (svn_fs_fs__p2l_index_append): s/iter_pool/iterpool/g.

* subversion/libsvn_fs_x/index.c
  (svn_fs_x__p2l_index_create): Same.

* tools/dev/fsfs-access-map.c
  (parse_file): Same.

git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1627498 13f79535-47bb-0310-9956-ffa450edef68