Instead of having two similar variants of RANAP_DirectTransfer:
- t(s|r)_RANAP_DirectTransfer, and
- t(s|r)_RANAP_DirectTransferSAPI,
let's make the first one more flexible, and drop the last one.
This is achieved by introducing two supplementary functions:
- f_gen_ts_dt_ies(), and
- f_gen_tr_dt_ies,
which dynamically compose DirectTransfer.protocolIEs.
Change-Id: I7333d08c4d5a72159bfbd50fe8e7b1084cd61b9e
e06f228be1