Add gtp-u tunnel creation at the CU side

- Change some elements names inside create_tunnel structure so that they are more generic to capture both N3 and F1-U use cases

openair2/LAYER2/PDCP_v10.1.0/pdcp.h

@@ -256,6 +256,21 @@ boolean_t pdcp_data_req(
   const uint32_t * destinationL2Id
 );
 
+boolean_t cu_f1u_data_req(
+  protocol_ctxt_t  *ctxt_pP,
+  const srb_flag_t srb_flagP,
+  const rb_id_t rb_id,
+  const mui_t muiP,
+  const confirm_t confirmP,
+  const sdu_size_t sdu_buffer_size,
+  unsigned char *const sdu_buffer,
+  const pdcp_transmission_mode_t mode
+#if (LTE_RRC_VERSION >= MAKE_VERSION(14, 0, 0))
+  ,const uint32_t *const sourceL2Id
+  ,const uint32_t *const destinationL2Id
+#endif
+  );
+
 /*! \fn boolean_t pdcp_data_ind(const protocol_ctxt_t* const, srb_flag_t, MBMS_flag_t, rb_id_t, sdu_size_t, mem_block_t*, boolean_t)
 * \brief This functions handles data transfer indications coming from RLC
 * \param[in] ctxt_pP        Running context.