libwebsockets

deprecation: remove lws_dll1

lws_dll2 has been available for a couple of years and lws_dll1 marked as
deprecated since v3.2.  Remove it.

If it affects you, lws_dll2 has an almost identical api but has more
features, such as storing in the lws_dll2_t which owner it is listed by
and keeping a count of objects on the list at the owner object.