fix KV data for postfix/local

[ulab]

The postfix_keyvalue_data that was generated by POSTFIX_LOCAL contained a string that could not be parsed as KV because it contained parts split by spaces that did not contain the = character:

...status=sent (delivered to command: procmail...

This PR changes it to use %{POSTFIX_SMTP_DELIVERY} instead which results in the correct format plus postfix_status and postfix_smtp_response fields.

While I am not sure if postfix_smtp_response is the correct name for a local transport, it is also used for POSTFIX_VIRTUAL and has the same meaning as in POSTFIX_SMTP.

[whyscream]

Hi @ulab,

I added a commit that copies the POSTFIX_SMTP_DELIVERY pattern and altered the pattern name. Maybe the same should be done for virtual, but we don't need to fix that here. What do you think?

[ulab]

I am "indifferent" 😉. On one hand it makes sense to use a different name for a different service message, on the other hand they have the same reason behind them.

But using a different name by default allows people to rename the field into a shared one with additional filters if they want to.