resolve: really always initialize aux

dns_transaction_request_dnssec_rr was already adjusted in 400171036592,
to allow for the return parameter to be passed uninitialized. However
this codepath was missed, meaning this function could sometimes return
success without having actually set the parameter.

Fixes: 400171036592 ("resolved: minor dnssec fixups")
Fixes: 47690634f157 ("resolved: don't request the SOA for every dns label")

src/resolve/resolved-dns-transaction.c

@@ -2347,9 +2347,9 @@ static int dns_transaction_request_dnssec_rr_full(DnsTransaction *t, DnsResource
                 r = dns_transaction_go(aux);
                 if (r < 0)
                         return r;
-                if (ret)
-                        *ret = aux;
         }
+        if (ret)
+                *ret = aux;
 
         return 1;
 }