net/sched: cls_flower: add support for matching tunnel control flags

extend cls_flower to match TUNNEL_FLAGS_PRESENT bits in tunnel metadata.

Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>