[sr-dev] mem leak using dispatcher in event route

Hi Kamailio devs,

we've found a memory leak in one of our servers: the AVPs filled by the dispatcher module's `ds_select_dst()` function, called in the `usrloc:contact-epired` event route are not freed.

Using this function in an event route is not encouraged by the documentation (only request/reply routes are mentioned there). However, it seems doable if we take care of the memory allocated for these AVPs.

My question is: how could this be done in this case? Is there some existing cleanup function that can be used in the registrar module, after the event route have been executed?