lwm2m: keep track of observations per client
this has a number of advantages:
- allows to only create notifications for each client if there are no
messages already waiting to be send, in practice prioritizing the
memory for messages for answers, thus staying more "responsive".
- saves a fair bit of memory by eliminationg now redundant client_ctx
pointer per observer.
- fixes a potential subtle bug: previously, an observer reset would've
stopped the first observation found with a matching token, which
might've belonged to a differen client.
Signed-off-by: Henning Fleddermann <henning.fleddermann@grandcentrix.net>
2 files changed
