Fix "unreachable code" warning.
Fix "unreachable code" warning.

* /subversion/libsvn_delta/compat.c
  (add_symlink_cb, alter_symlink_cb, rotate_cb): SVN__NOT_IMPLEMENTED
   does an unconditional return; so remove the trailing return SVN_NO_ERROR

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