Changes

ranap: Support Tx GlobalRNC-ID during RANAP RESET (ACK)

This commit doesn't affect the behavior of any existing testsuite yet,
it only updates the templates and adds a RanOps param to be able to pass
a GlobalRNC-Id to RAN_Emulation.

A follow-up commit will change SGSN_Tests to append GlobalRNC-Id to
RANAP Reset when sending towards SGSN, since it's mandatory for an RNC
to set it according to 3GPP TS 25.413 8.26.2.2.

Change-Id: I0628e412bdff6ed8eefe9051ec351fbd1d0b634f

Include GlobalRNC-ID IE during Tx RANAP Reset towards SGSN

An RNC shall include this IE during RANAP Reset, as specified in
3GPP TS 25.413 8.26.2.2.

Change-Id: Ic16817a2064fa87b80a81b07868005069d67aec2

testenv: don't use all RAM in 5gc testsuite build

When building the 5gc testsuite with as many parallel jobs as CPU cores
are available (the default), on at least Pau's and my system, all RAM
gets consumed and the system becomes unusable. On other systems, an
out-of-memory killer might kill the compiler, which is also not great.
This can currently only be avoided if the user remembers to pass "-j4"
to testenv, to ensure that only 4 jobs run in parallel.

Add a new max_jobs_per_gb_ram= option to 5gc/testenv.cfg. Set it to 0.3,
so on e.g. systems with 15 GiB of RAM, we get 4 jobs as maximum.

Change-Id: I1b9c9a2e3fa244337342e95457ac6d3a8caa0ae6

sgsn: Add suport to obtain statsd output

It will be used in a follow-up commit in TC_stat_rnc_sctp_disconnected.

This new test infrastructure can still be used with osmo-sgsn latest
since it already initialized the statsd VTY commands despite having no
osmo_stats in use.

Change-Id: Ic86ce75ea700d05fc65fcea3cdab7b7eaac12069