sm: Don't mark a cert as de-vs compliant if it leads to SHA-1 sigs.

* sm/keylist.c (print_compliance_flags): Also check the diges_also.

A certificate with algorithm sha1WithRSAEncryption can be de-vs
compliant (e.g. if the next in the chain used sha256WithRSAEncryption
to sign it and RSA is long enough) but flagging it as such is useless
because that certificate can't be used because it will create
signatures using the non-compliant SHA-1 algorithm.

Well, it could be used for encryption. But also evaluating the
key-usage flags here would make it harder for the user to understand
why certain certificates are listed as de-vs compliant and others are
not.

• Signed-off-by: Werner Koch <wk@gnupg.org>