Enable avatars for xmpp chat rooms

src/freedombone-app-xmpp

@@ -775,6 +775,7 @@ function xmpp_modules {
       echo '  "pep"; -- Personal Eventing Protocol (to support OMEMO)';
       echo '  "omemo_all_access"; -- Fix for PEP with OMEMO';
       echo '  "vcard"; -- Personal Eventing Protocol (to support OMEMO)';
+      echo '  "vcard_muc"; -- Avatars for chat rooms';
       echo '  "e2e_policy"; -- To support OMEMO';
       echo '  "pep_vcard_avatar"; -- Personal Eventing Protocol (to support OMEMO)';
       echo '  "blocklist"; -- Privacy lists';