hiding pkg-config

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

What's the best way to hide pkg-config by default?

We often have build breakage for new packages where the package was
not tested in a clean environment, and used an installed copy of
pkg-config.

I'd like to have a default pkg-config in the path (if pkg-config is
not in USE_TOOLS) that e.g. maps to 'false'. Does anyone know off-hand
what's the best way to do that is, or if there's a better way?

Thanks,
 Thomas