unit_tests: Remove useless wrapping for argv/buffer tests

unit_tests: Remove useless wrapping for argv/buffer tests

If not using mock() or check_expected(), and
not linking the original function, then there
is no need for wrapping support.

Change-Id: I937105abeb5e8f796bf6bbe8432972adb60b3e2a
Signed-off-by: Frank Lichtenheld <frank@lichtenheld.com>
Acked-by: Gert Doering <gert@greenie.muc.de>
Gerrit URL: https://gerrit.openvpn.net/c/openvpn/+/1243
Message-Id: <20251007185217.19381-1-gert@greenie.muc.de>
URL: https://sourceforge.net/p/openvpn/mailman/message/59243508/
Signed-off-by: Gert Doering <gert@greenie.muc.de>