SASL readme smtp/smtpd confusion

[Jasper Jongmans]

The SASL readme section "Postfix SMTP/LMTP client policy - SASL
mechanism properties"
<http://www.postfix.org/SASL_README.html#client_sasl_policy>, subsection
"Encrypted SMTP session (TLS)", mentions smtpd_sasl_security_options and
smtpd_sasl_tls_security_options, but I think their smtp_ equivalents are
meant instead.