1. Create a free_ru_session_list() function to free the memory allocated for the connected RUs
before closing the nr-softmodem.
2. xmlReadMemory() and xmlNodeGetContent() were causing serious memory leakages,
and now all is properly freed using xmlFreeDoc() and xmlFree().
Introduced a parameter start_up_timing which indicates if PM activation is supported during the start-up
procedure. We initialize this parameter, based on the vendor.
Notification interval is set to 10s.
Teodora