Fix swig perl bindings on Windows.

* subversion/bindings/swig/perl/libsvn_swig_perl/swigutil_pl.c
  (svn_swig_pl_array_to_apr_array_revision_range): Include a return to avoid
    Visual Studio erroring out saying that some code paths the function doesn't
    return a value.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1480119 13f79535-47bb-0310-9956-ffa450edef68