Refactor processing of sdap_Config in add_drb (PDCP)

* use get_sdap_Config to process sdap_Config
* move SDAP config logic to the scope where it is relevant
* add SDAP entity direcly in RRC, not from PDCP
* replaced nr_pdcp_add_drbs with single add_drb call: it was no longer
  efficient to keep it in the new logic. The addMod list can be looped directly in RRC.
* add specific function to add bearers from addMod list in E1, NSA, and UE

openair2/SDAP/nr_sdap/nr_sdap_entity.h

@@ -77,7 +77,7 @@ typedef struct qfi2drb_s {
 
 void nr_pdcp_submit_sdap_ctrl_pdu(ue_id_t ue_id, rb_id_t sdap_ctrl_pdu_drb, nr_sdap_ul_hdr_t ctrl_pdu);
 
-typedef struct {
+typedef struct sdap_configuration_s {
   int pdusession_id;
   int drb_id;
   bool sdap_rx;