The HS_DESC event was using rend_data_t from the dir connection to reply the
onion address and authentication type. With the new HSFETCH command, it's
now possible to fetch a descriptor only using the descriptor id thus
resulting in not having an onion address in any HS_DESC event.
This patch removes rend_query from the hs desc control functions and replace
it by an onion address string and an auth type.
On a successful fetch, the service id is taken from the fetched descriptor.
For that, an extra parameter is added to "store as a client" function that
contains the cache entry stored.
This will make the control event functions scale more easily over time if
other values not present in rend_data_t are needed since the rend_data from
the dir connection might not contained everything we need.