Log Message:
pkgtools/pkglint: update to 20.2.1

Changes since 20.2.0:

Don't warn about a possibly redundant PKGNAME=${DISTNAME} assignment if
PKGNAME is defined somewhere else in the package Makefile.

Warn if NO_CONFIGURE=yes and REPLACE_* are combined.

Suggest to replace ${VAR:@l@-l${l}@} with the simpler ${VAR:S,^,-l,},
as well as ${VAR:@l@${l}suffix@} with the simpler ${VAR:=suffix}.

Allow lua in CATEGORIES.