Log Message:
kermit: fix compilation on Linux with glibc >= 2.28

Fix taken from the upstream project's 9.0.305 Alpha.01 release, noted to
be a temporary workaround. (Separately, from how I read the change log,
there has been no stable 9.0 release since 9.0.302.) Tested on Debian
9.13 (which has an older version of glibc which wouldn't reproduce the
issue) and Fedora 31 & 32.

(This issue was reported on pkgsrc-users back in July 2019 by Pierre
Dupond, and I'd provided a workaround for it in that email chain, but
I'd never actually committed anything to pkgsrc.)