Before this commit, pdcp_data_ind is done in the realtime PHY/MAC
thread, and this may have an impact on realtime performances.

Let's introduce a new thread to do the job, freeing the realtime
PHY/MAC logic.

This is not a minor change. It may have positive and/or negative
effects. To be tested carefully.

MR !1333: Docker: reduce the number of layers in target images. 
 
MR !1345: small fixes for nr rlc
-trigger status report when t-reassembly expires
-reduce "buffer full" log

Fix Msg4 segmentation fault when UE_id is invalid and reset ul_failure when UE reconnects using C-RNTI

and update tests that fail because of the new logic

Revert "Schedule PUCCH even when ul_failure, otherwise COTS UE cannot use Msg3 to transfer DCCH messages"

This reverts commit c9007ee7

MR !1336 : Handle Msg3 carrying a DCCH or DTCH message
This MR implements the procedures for gNB to handle a Msg3 carrying a DCCH or DTCH message. 
For example, when a new RA happens and the UE is already known by the network.

MR !1337 : Fix build warning
Fix a build warning in develop related with a comparison between ‘X2AP_ResetRequest_IEs__value_PR’ {aka ‘enum X2AP_ResetRequest_IEs__value_PR’} and ‘enum X2AP_Cause_PR’

MR !1330 : nr rlc: speedup buffer status computation
TX and ReTX should be faster now (for RLC AM, UM and TM).
RLC AM Status (function nr_rlc_entity_am.c:status_size()) was not modified, so its CPU usage is the same as before

MR !1276 : NR ACKNACK improvements
This MR improves acknack_scheduling, includes in config file min delay for acknack feedback and fixes bugs in acknack procedures at UE

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

branch : integration_2021_wk48_d

MR !1308 : Nr add ue improvements-

MR !1310 : parallelization of LDPC decoding on UE side
-fixes the issue of parallelization of LDPC decoding on UE side

MR !1331 : T tracer: trace MAC DL retransmission PDUs in the gnb
-trace MAC DL retransmission PDUs in the gnb
-adapt macpdu2wireshark to deal with them

MR !1306 : fix for harq value in fapi indication according to scf
-We were using harq value in the wrong way. According to SCF it is 0 for pass and 1 for fail


CI fixes : 
proper way to address B200 serial number for eNB/gNB
missing library when running uhd_find_devices in container