Add Fedora 34 support

* update the support distro filter

* don't install xinetd which doesn't exist in F34 any more.  I think
  there is probably a bit more to do with swift ring-server but that
  can be a problem for another time.

* remove old F31 workaround

Change-Id:If2f74f146a166b9721540aaf3f1f9fce3030525c
diff --git a/files/rpms/swift b/files/rpms/swift
index 376c6f3..18c957c 100644
--- a/files/rpms/swift
+++ b/files/rpms/swift
@@ -4,4 +4,4 @@
 rsync-daemon
 sqlite
 xfsprogs
-xinetd
+xinetd # not:f34