This stops all ongoing threads (using pthread_join()), and marks FIFOs
to not block anymore. In this case, returned messages will be NULL.

A detached thread cannot be joined with pthread_join(). However, this
is crucial for correct resetting of the nr-softmodem. Therefore, do not
create threads in detached state.

- First stop threads then free memory
- Don't call kill_NR_RU_proc() twice (is called in stop_RU())
- Memory allocation optimizations

integration_2022_wk32

See merge request oai/openairinterface5g!1658

MR !1551 Use F1 internally: RRC Message Transfer
MR !1645 fix(ci): Fixes for the legacy LTE bench
MR !1654 Fix for NDI init at UE
MR !1656 ngap: minor fix: access the array correctly
MR !1635 Fix SDAP in RFSIM mode
MR !1643 add asn1c logs
MR !1647 Function to get sample rate and BW

 - Problem with escaping chars
 - Killing properly tshark process on EPC
 - standalone Terminate eNB was failing
Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>