Remove dead code

[sune-ext-lyngby]

We patched in this logging point earlier, but once the event is created,
it will be accepted by the event queue, and thus it must have an ID, so
this cannot fail.
No need to have this customization point.

[sune-ext-lyngby]

I think this might be more correct than #40

[Emil-Juhl]

I can see that the queue_full function is overridden inside mozart-fep in EventQueueLogging. Now, I don't know if that means that it is called from theses places, but a grep in this fork of mbed seems to show that these are the only callsites for this particular function.
I know there was added some logging related to queue being full recently, but that seems to depend on the return value of event_queue.call (see HostHandler.cpp:1378 in mozart-fep)

I am not confident approving or not-approving this currently. Might look more into it later, but I think a FEP-guru should take a look

[sune-ext-lyngby]

queue_full is also called a bit earlier in all the same functions when we notice that queue is full.