* src/tgbatest/kv.test, iface/nips/nipstest/dotty.test: Don't rely
on the ${DOT-...} syntax, because DOT is always set and might be
set to the empty value.
access to that host.
* src/tgbatest/kv.test: Use ${DOT-true} instead of ${DOT-:}. I
don't know, the MacOS shell must be mixing the syntaxes for
${DOT:-} and ${DOT-:}.
* iface/nips/nipstest/dotty.test: Likewise