Merge remote-tracking branch 'origin/assigned_value_is_garbage_or_undefined' into integration_2023_w43

- Set the correct QoS flow ID to associate a correct QoS flow to the
  bearer: the UE would misassociate otherwise
- Set the DRB as the default: the handler applies bool with true==1, so
  use bool value

Introduce a --no-itti-threads command line option to disable threading
in ITTI, and call message handlers in the current thread. This is being
introduced in order to increase repeatability when testing the nrUE with
the IQPlayer. Without this feature, runs with the IQPlayer will end up
differently, depending on the timing of ITTI threads, mostly when
sending messages to RRC and NAS.

Messages are pushed using pushNotifiedFIFO(), so we pullNotifiedFIFO()

Before this commit, the DMRS_UplinkConfig was stored in a separate
DMRS-related structure, although it is always referenced in the
PUSCHConfig of the current UL BWP.

Through certain code paths (e.g., retransmission), it could happen that
an old DMRS_UplinkConfig was accessed that was freed (through new
CellGroupConfig).

In this commit, we always look up the DMRS_UplinkConfig in the current
PUSCH config, which should always be up to date.

Until this commit, the SIB1's PDCCH_configCommon was set (via a pointer,
i.e., an indirection) to the one of the ServingCellConfigCommon (SCC).
Afterwards, the SIB1 code further populated this PDCCH configCommon,
indirectly populating the one of the the SCC, on which code later
depends.

Not only did this create possibilities for double-frees (since freeing
the memory of SIB1, then SCC would free the PDCCH configcommon twice),
but also it makes it harder to track where certain structures are
populated. Hence, this commit solves both issues:

- The SCC is correctly populated on initialization of the SCC
- The SIB1 makes a deep copy of the SCC' PDCCH configCommon

This resolves the two issues above.

Not initalizing this struct makes asn1c free the memory incorrectly,
leading to a segfault.

- harmonize monolithic and E1AP case
- use ITTI message to send bearer context setup response to RRC

This allows to communicate with multiple remote hosts. A further
improvement would be to refactor this piece of code into a function and
call it only when necessary, i.e., when we know the remote host, or want
to add one to a list of hosts.