Log Message:
postfix: Update to 3.5.6

upstream changes:
-----------------
Fixed in Postfix versions 3.5.6, 3.4.16, 3.3.14, 3.2.19:

  * One fix for memory leaks in the Postfix TLS library was back-ported to the \ 
wrong place, resulting in undefined program behavior.

Fixed in Postfix versions 3.5.6, 3.4.16:

  * The workaround for allowed TLS protocol versions did not explictly override \ 
the system-wide OpenSSL configuration, for sessions where the remote SMTP client \ 
sends SNI. It's better to be safe than sorry.

 Fixed in Postfix versions 3.5.5, 3.4.15, 3.3.13, 3.2.18:

  * Workaround for unexpected TLS interoperability problems when Postfix runs on \ 
OS distributions with system-wide OpenSSL configurations.

  * Memory leaks in the Postfix TLS library, the largest one involving multiple \ 
kBytes per peer certificate.