In case no MAC CE needs to be transmitted and we filled the buffer with SDUs from RLC, we missed to add padding for the last 3 bytes.

- restored FIXED subheader length
- restored SHORT subheader in MAX TBS (still unclear the reason behind the
  selection of SHORT subheader here by developer)

- send C-RNTI MAC CE otherwise
- init RA if there are bytes to send and is a PRACH occasion
- minor cleanups

- TC-RNTI is set and used after RAR reception according to the specs
- C-RNTI is used in CFRA

- takes in input MAC instance
- uses a mac ce struct
- minor fixes

- removed code from outside this function
- generate random padding in RFSIM mode
- generate 0 padding in real-time
- padding is generated either to complete the PDU or to transmit a new one
  when no data from RLC was fetched

- set constant variables to const

- improved debug logging
- minor fixes and cleanup

- this prevents crashes when the function is called for LCIDs that have no RB
- and simply print error message and return 0 when no RB is found

- included MAC CE sub-PDUs size in the computation of RLC data to transmit
  this fixes the error with residual mac pdu appearing at gNB side when
  transmitting higher amount of data
- got rid of the nr_generate_ulsch_pdu and moved the relevant UL-SCH MAC PDU
  generation procedure within the nr_ue_get_sdu and nr_ue_get_rach
- reduced memcpy calls and unnecessary memory allocations
- fetching RLC data and SDU size from the mac_rlc_data_req, removed the call
  to mac_rlc_get_buffer_occupancy_ind
- introduced a new function to generate the MAC CEs sub-PDUs
- removed unnecessary function input parameters
- minor fixes and cleanup
- enhanced logging

- Fix the SA RF test (wrong conf file)
- No more copy of RAW files in SA
- Fix no-detection of failures on RA
Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>

integration_2021_wk31

See merge request oai/openairinterface5g!1219

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

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

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

MR !1206 : nr_ue_remove_high_speed_flag
This flag is always set to 1, 
With multiple DMRS symbols configuration, very recent DMRS containing symbol shall be for channel estimation.

MR !1205 : fix-lte-ue-modem-in-docker-container
We bind the socket to any_addr (instead of localhost), so the commands to the UE can come also from a remote machine

MR !1178 : NR_CSIRS_tomerge
Implementation of CSI RS transmission at gNB

MR !1211 : develop-NSA_SA_fixes
Small fixes for NSA and SA

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

Merge remote-tracking branch 'origin/fix-lte-ue-modem-in-docker-container' into integration_2021_wk30