Fix swig-pl on trunk on OS X.

* subversion/bindings/swig/perl/native/Makefile.PL.in
  (@ldpaths): fs_x needed to be added. 


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1535609 13f79535-47bb-0310-9956-ffa450edef68