MR !1354 : Fix msg4 segfault
- Fix segmentation fault that happens after an uplink failure timeout (gNB removes the UE) and when UE tries to use the same (old) RNTI.

MR !1347 : nr pdcp: introduce a thread to do pdcp_data_ind
- Before this commit, pdcp_data_ind is done in the realtime PHY/MAC thread, and this may have an impact on realtime performances.
- introduce a new thread to do the job, freeing the realtime PHY/MAC logic.

MR !1360 : Scope telnet fixes
-no need for form.h header in telnet 
-enable double buffering in scope 
-freeze gNB scope while updating graphs

MR !1363 : CI: a few fixes
-Increased some timeout 
-Added missing gNB log file from artifact

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

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

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

Change the python script such that we first build the ran-base image
(renamed from ran-build, as it does not build anything), followed by the
ran-build image compiling all dependencies, and the generate the
independent target container images.

This commit creates an intermediary build image for all eNB, gNB, UE,
nrUE, RU targets (ran-build) after the image containing all RAN
compilation dependencies (ran-base). Then, the corresponding target
container images are just copied from the ran-build.

The only exception is phySim, which is still compiled independently, as
the build_oai would otherwise put all compiled files into
phy_simulators/build instead of ran_build/build. We do this at this
state to avoid any inconsistencies.

This commit creates an intermediary build image for all eNB, gNB, UE,
nrUE, RU targets (ran-build) after the image containing all RAN
compilation dependencies (ran-base). Then, the corresponding target
container images are just copied from the ran-build.

- Remove useless RU and PHYSIM variables
- provide function to trigger ASN.1 file generation