Function dcpc_program_event

* dcpc_program_event() can be called owing to a new enabling or if a multi * overflow platform has disabled a request but needs to program the requests * that are still valid. * * Every invocation of dcpc_program_event() will create a new kcpc_ctx_t * and a new request set which contains the new enabling and any old enablings * which are still valid (possible with multi-overflow platforms).