Fix build of swig bindings when --with-serf is defined: remove the trailing '\' of the serf include path as it'll break the swig build step.
Fix build of swig bindings when --with-serf is defined: remove the
trailing '\' of the serf include path as it'll break the swig build step.

* build/generator/gen_win.py
  (get_win_includes): don't add trailing '\' to serf include path.

Approved by: jerenkrantz

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion