journal: do not clear individual fields if the struct won't be reused

Especially that only some of the fields are cleared currently.

src/journal/journalctl-show.c

@@ -35,8 +35,8 @@ typedef struct Context {
 static void context_done(Context *c) {
         assert(c);
 
-        c->synchronize_varlink = sd_varlink_flush_close_unref(c->synchronize_varlink);
-        c->event = sd_event_unref(c->event);
+        sd_varlink_flush_close_unref(c->synchronize_varlink);
+        sd_event_unref(c->event);
         sd_journal_close(c->journal);
 }
 

src/journal/journald-sync.c

@@ -138,7 +138,7 @@ SyncReq* sync_req_free(SyncReq *req) {
                         LIST_REMOVE(pending_rqlen, req->server->sync_req_pending_rqlen, req);
         }
 
-        req->idle_event_source = sd_event_source_disable_unref(req->idle_event_source);
+        sd_event_source_disable_unref(req->idle_event_source);
 
         sd_varlink_unref(req->link);