- comments to improve readability of the code
- Clang formatting of E1 / RRC (partial)

- new folder dedicated to E1AP docs
- new file to document E1AP procedures

- PDCP reestablishment on CUCP (DRBs) triggering Bearer Context Modification procedures over E1
- Performing PDCP reestablishment for requested DRBs on CUUP
- Introduced function to notify re-establishment to CU-UP
- removed call to PDCP reestablishment for the DRBs on CUCP (it's done on CUUP)

cuup_notify_reestablishment:

- to fetch PDU session to setup in E1 following logic as in e1_send_bearer_updates
- fill bearer context modification request with stored F1-U tunnel information
  during E1 reestablishment, otherwise it would initialized to 0 by default
- update GTP tunnel with the stored configuration after E1 reestablishment

- info coming from UE context setup/modification response messages in RRC

The following ASSERT is tirggered while testing 16 UE setup.

Assertion (NPRB>0 && (NPRB + RBstart <= BWPsize)) failed!
In PRBalloc_to_locationandbandwidth0() /home/ran/common/utils/nr/nr_common.c:286
Illegal NPRB/RBstart Configuration (1,48) for BWPsize 48

Corrected the get_start_stop_allocation calculation to fix the issue.
The implementation was wrong. The rbstop shall be the last rb that could
be allocated. Also the following two conditions are taken care

rbStart needs to be strictly smaller than rbStop

rbStart+rbSize needs to be smaller or equal to rbStop

The problem was that we confounded both conditions, so rbStart could
be equal to rbStop, which then leads to one PRB being allocated at the end.
Setting rbStop to BWPsize - 1 and making sure the above two conditions are
true does not make it lead to wrong allocations anymore.

textlog is, well, text log. The GUI part is totally useless.
Let's remove it.

The previous code removed the "secondary UE" data (about DU association,
DU UE ID, associated CU UP), and only filled the F1-related data. In
other words, the associated CU-UP was lost. This commit reworks this
piece of code to retrieve old data, and update the relevant data without
destroying other.

- many structs and definitions are overlapping between the two different E1 procedures
- introduced naming specific to E1 Bearer Context Modification to improve readability
- grouped SDAP and PDCP configuration IEs for better reusability and readability
- introduced functions to set and get default PDCP config (DRBs and Bearer Contexts)

find_or_next_pdu_session:
- find_or_next_pdu_session refers to the E1 Bearer Context Modification Request
-- therefore it has to return pdu_session_to_mod_t* and takes in input e1ap_bearer_mod_req_t *

see !MR2545 for more context

- according to specs, in NR there are 4 SRBs
- in OAI the relevant define is used in the RRC procedures
- this commit harmonizes code by removing redundancy

- the goal is to improve maintanability

CI: Integration Branch 2024 week 08

See merge request oai/openairinterface5g!2585

* !2540 NR UE max MIMO layers from UEcap
* !2554 NR UE RRC minor improvements
* !2563 Add missing backtick for proper code style in README.md
* !2567 Avoid integer overflows, buffer overflows, in channel levelling
* !2574 NR UE fix for configuring coreset0 and SS0
* !2575 NR UE fix init PDCP phy-test
* !2551 NR UE improvements for contention resolution timer
* !2570 CI: Replace nrmodule2 by up2

This reverts commit 2b796874.

Merge remote-tracking branch 'origin/fix-multiple-inexact-computations-in-nr_dlsch_channel_level' into integration_2024_w08

Add missing backtick for proper code style in README.md: on behalf of Roger Pueyo Centelles, MR 2563
Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

UBsan fails with errors without this commit. The commit changes:

- avoid two possible integer overflows in nr_dlsch_channel_level() and nr_dlsch_channel_level_median()
- nr_dlsch_channel_level_median() is simplified
- use MAX_ANT in avg to handle more than 4x4 config