Log Message:
lintpkgsrc: Update pkgtools/lintpkgsrc to 4.94

pkgsrc changes:
 - Use SUBST_VARS instead of SUBST_SED to adjust the several variables in
   files/lintpkgsrc.pl and avoid some make contortionism in the remaining
   SUBST_SED

Changes:
 - PKG_SYSCONFDIR can be different to ${PREFIX}/etc, instruct lintpkgsrc
   about that to possibly pick mk.conf when an /etc/mk.conf file is not
   available

Discussed on pkgsrc-changes@ with <adam> and <jperkin>.
Thanks to both <adam> and <jperkin> for feedback, suggestions and review!