Merge remote-tracking branch 'origin/interop-srsran-du' into integration_2025_w34 (!3550)

some work for better interoperability with srsRAN DU

Just add the minimum to get some user plane traffic going on.

When doing user plane traffic, in the CU logs we have a lot of:

    [GTPU]   NR-RAN container type: 1 not supported

That will be fixed in another MR, not here.

CMakeLists.txt

@@ -1396,9 +1396,10 @@ include_directories("${OPENAIR1_DIR}/SCHED_NR_UE")
 add_library (GTPV1U
   ${RRC_DIR}/rrc_eNB_GTPV1U.c
   ${OPENAIR3_DIR}/ocp-gtpu/gtp_itf.cpp
+  ${OPENAIR3_DIR}/ocp-gtpu/gtpu_extensions.c
   )
 target_link_libraries(GTPV1U PRIVATE asn1_nr_rrc_hdrs asn1_lte_rrc_hdrs)
-target_link_libraries(GTPV1U PRIVATE SIMU)
+target_link_libraries(GTPV1U PRIVATE SIMU ds)
 include_directories(${OPENAIR3_DIR}/ocp-gtp)
 
 set (MME_APP_SRC