[syslog-ng] [PATCH (3.4) 0/3] afsql code cleanups

[Gergely Nagy]

The patches following this mail are my attempts at cleaning up the
afsql driver here and there, mostly afsql_dd_insert_db(), in
preparation for moving towards LogThreadedDestDriver (which will be
posted separately a bit later).

The migration is possible without these patches, but these are worth
applying even without the LogThreadedDestDriver patches, as these
present no real architectural change, just a little refactoring.

I think the code could be cleaned up further, but for the time being,
I only did what I thought necessary to prepare for migration to
LogThreadedDestDriver.