Remove unused structure from JavaHL.

* subversion/bindings/javahl/native/InfoCallback.h,
  subversion/bindings/javahl/native/PatchCallback.h (info_entry):
   Remove unused forward declaration.

* subversion/bindings/javahl/native/SVNClient.cpp (info_baton):
   Remove unused type declaration.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1527830 13f79535-47bb-0310-9956-ffa450edef68