Log Message:
pkgtools/pkglint: update to 20.1.5

Changes since 20.1.4:

No more wrong warnings about the Solaris /bin/sh. These warnings had been
there for 14 years, preventing pkgsrc developers from using the $$(...)
command substitution and negation in shell conditions.

https://mail-index.netbsd.org/pkgsrc-changes/2020/05/01/msg212194.html