mail/postfix: update to 3.5.4

Update postfix to 3.5.4.

Fixed in Postfix 3.5.4, 3.4.14:

  * The connection_reuse attribute in smtp_tls_policy_maps always
    resulted in an "invalid attribute name" error. Fix by Thorsten
    Habich.

  * SMTP over TLS connection reuse always failed for Postfix SMTP
    client configurations that specify explicit trust anchors (remote
    SMTP server certificates or public keys). Reported by Thorsten
    Habich.

Fixed in Postfix versions 3.5.4, 3.4.14, 3.3.12, 3.2.17:

  * The Postfix SMTP client's DANE implementation would always send
    an SNI option with the name in a destination's MX record, even
    if the MX record pointed to a CNAME record. MX records that
    point to CNAME records are not conformant with RFC5321, and so
    are rare.

    Based on the DANE survey of ~2 million hosts it was found that
    with the corrected SMTP client behavior, sending SNI with the
    CNAME-expanded name, the SMTP server would not send a different
    certificate. This fix should therefore be safe.

(taca)