Fix a trivial log message error in renservice.c

Fixes bug 4856; bugfix on 0.0.6

This bug was introduced in 79fc5217, back in 2004.

changes/bug4856

@@ -0,0 +1,3 @@
+  o Trivial bugfixes
+    - Fix a typo in a log message in rend_service_rendezvous_has_opened().
+      Fixes bug 4856; bugfix on Tor 0.0.6.

src/or/rendservice.c

@@ -1564,7 +1564,7 @@ rend_service_rendezvous_has_opened(origin_circuit_t *circuit)
                 circuit->rend_data->rend_pk_digest);
   if (!service) {
     log_warn(LD_GENERAL, "Internal error: unrecognized service ID on "
-             "introduction circuit.");
+             "rendezvous circuit.");
     reason = END_CIRC_REASON_INTERNAL;
     goto err;
   }