Fix binary and (&) used in auth-token check instead of logical and (&&)

Fix binary and (&) used in auth-token check instead of logical and (&&)

AUTH_TOKEN_HMAC_OK is 1, so the first term is always 0/1 and the bool
from the second part is also 0/1, so the & does the same in this instance
as &&.

In this specific case & instead && does not change behaviour but using
&& is the intended semantic behaviour.

Signed-off-by: Arne Schwabe <arne@rfc2549.org>
Acked-by: Gert Doering <gert@greenie.muc.de>
Message-Id: <20210331155508.19423-1-arne@rfc2549.org>
URL: https://www.mail-archive.com/openvpn-devel@lists.sourceforge.net/msg21911.html
Signed-off-by: Gert Doering <gert@greenie.muc.de>