Obtained from: Maintainer (partly)
modify the Makefile to use PLIST.mule if USE_MULE is defined. This
will allow the version with mule to be successfullt packaged and
pkg_delete'd.
Add a warning, obtained from the Maintainer, in the case where
HAVE_MOTIF is defined but MOTIF is really lesstif. It seems that
some users have seen problems with that constellation.
Add pkg/PLIST.mule to be used for the mule version.
Satoshi forgot to close the PR when he made his commit for the
reported problem with generating a version with mule.