#5105 Fix "missing TLS key file" error in case smtpd does not use tls

[Ralf Habacker]

In the postfix section "SMTP Authentication And Encryption" I tried to configure
"Use SASL SMTP authentication" for german provider strato, which requires to set
relayhost, smtp_sasl_auth_enable, smtp_sasl_password_maps and smtp_sasl_security_options (see http://www.dirk-hagedorn.de/?page_id=789). After entering the requested values on saving the section I got an error "missing TLS key file", although "Enable TLS encryption" has been set to none or default (which is none according to http://www.postfix.org/postconf.5.html#smtp_tls_security_level)

The appended patch fixes the issue by only checking presence of TLS related files if TLS encryption is enabled.

[Kay]

hallo Ralf,

TLS may also used with SASL when authentating agianst external servers, but I can't check because I dont use sasl in this context.

may be you can provide a PR on GitHub, so it's easyer review and integrate. https://github.com/webmin/webmin

Frohe Ostern!