Use F1 UE context setup/modif Request in stack

Use the new, tested F1 UE context setup request and modification
requests in the stack.

We have to do both at once, because there are some functions that are
used by handlers for both messages, notably

- handle_ue_context_drbs_setup()
- handle_ue_context_srbs_setup()

(+ and some functions called by those two). For instance, the first uses
the (new/old) type f1ap_drb_to_be_setup_t/f1ap_drb_to_setup_t which is
shared. The alternative would be to duplicate the functionality
temporarily, and I want to avoid unnecessary code churn.

openair2/F1AP/f1ap_cu_task.c

@@ -36,6 +36,7 @@
 #include "f1ap_cu_ue_context_management.h"
 #include "lib/f1ap_rrc_message_transfer.h"
 #include "lib/f1ap_interface_management.h"
+#include "lib/f1ap_ue_context.h"
 #include "f1ap_cu_paging.h"
 #include "f1ap_cu_task.h"
 #include "openair2/RRC/NR/nr_rrc_defs.h"
@@ -186,13 +187,13 @@ void *F1AP_CU_task(void *arg) {
         break;
 
       case F1AP_UE_CONTEXT_SETUP_REQ: // from rrc
-        CU_send_UE_CONTEXT_SETUP_REQUEST(assoc_id,
-                                         &F1AP_UE_CONTEXT_SETUP_REQ(received_msg));
+        CU_send_UE_CONTEXT_SETUP_REQUEST(assoc_id, &F1AP_UE_CONTEXT_SETUP_REQ(received_msg));
+        free_ue_context_setup_req(&F1AP_UE_CONTEXT_SETUP_REQ(received_msg));
         break;
 
       case F1AP_UE_CONTEXT_MODIFICATION_REQ:
-        CU_send_UE_CONTEXT_MODIFICATION_REQUEST(assoc_id,
-                                                &F1AP_UE_CONTEXT_MODIFICATION_REQ(received_msg));
+        CU_send_UE_CONTEXT_MODIFICATION_REQUEST(assoc_id, &F1AP_UE_CONTEXT_MODIFICATION_REQ(received_msg));
+        free_ue_context_mod_req(&F1AP_UE_CONTEXT_MODIFICATION_REQ(received_msg));
         break;
 
       case F1AP_UE_CONTEXT_RELEASE_CMD: // from rrc