* tests/openpgp/defs.scm:  We expect that stuff is now installed.
(tools): Fix the names.
(intsalled?, bin-prefix): Remove.
(tool-hardcoded): Simplify.
(gpg-conf'): Simplify.
(GNUPG_BUILDDIR): Do not anymore set this envvar.
* tests/tpm2dtests/defs.scm: Ditto.