[S] Change in osmo-mgw[master]: mgcp_client_fsm: allocate struct mgcp_conn_peer dynamically

dexter has abandoned this change. ( https://gerrit.osmocom.org/c/osmo-mgw/+/34404?usp=email )

Change subject: mgcp_client_fsm: allocate struct mgcp_conn_peer dynamically ......................................................................

Abandoned

As far as I remember (by the comments) the context was that we wanted to allocate mgcp_conn_peer dynamically to lower the risk with ABI/memory size problems in the future. However, the price would have been to make an incompatible API change now. Given that the patch is very old and we apparently have no problems with, let's abandon it.