modules/workarounds: fix module initialisation.

Firstly, I needed to fix the module initialisation otherwise nothing was happening at all.

It seems it's been broken for a while. I needed to rename config to init, which is called when a module is loaded.

Then I realised that setting NO_EDNS like NO_0X20 is set in other cases, resulted in SERVFAIL, so I have added a begin layer function for these specific cases.

An example query is A 1.1.1.2.rbl.rbldns.ru.

rbl.rbldns.ru needs NO_EDNS otherwise it doesn't reply at all (resulting in SERVFAIL because of UDP and TCP timeouts) and causes the query to be repeated because of QNAME minimisation.