Replace logging callback interface

[jptosso]

Coraza and modsec logging works differently, which presents a challenge for libcoraza. In modsec, there logger callback per transaction, while in coraza there is a general error log callback.

1. We need to set up a friendlier callback, modsec void is not properly documented, and it is weird.
2. In the meantime we can use waf loggers instead transaction logger, but that will mean logs won't be aware of custom error logs in nginx for specific URLs or others, there will be only one error log per coraza context
3. Make current log callback work for Coraza, it is just a placeholder, it is not working.