Also changed logic in the NR UE schedule to read
IP traffic. Also, configured the RLC layer in the
NR UE softmodem and the DRBs with the cRNTI once
the RACH procedure is complete in the NR UE.

Updated the configuration files. Added a sleep to
ensure that the LTE UE gets attached to the EPC
before the bearer is modified to be gNB. Updated
the ifconfig tunnel up command to be brought up
by the NR UE socket when in NSA mode. Lastly,
started the gNB PDCP layer in S1 mode.

Once the LTE UE's tunnel interface with the EPC
is ready to be established, if we are in NSA mode,
we do not want to launch the tunnel interface
from the LTE UE side, but in the NR UE. Via itti_msgs
we send the string containing the tunnel interface
'up' command to the NR UE and bring it up from the NR UE.

This commit has several other changes. The changes
include the following:
1. Changed the port numbers for the NRUE<->Proxy
2. Fixed the send to function in the NR UE
   (Previously only sending buffer not buffer+msg_type)
3. Updated pack/unpack of the SSB PDU (new RSRB field added)
4. Fixed several NR logs
5. Opening socket with NRUE<->Proxy AFTER receving RRC
   measurement request from the LTE UE

This commit also removed MAX_NUM_NEIGH_CELLs and
replaced it with MAX_GNB_CELLS. This was a minor change
OAI added. The standalone sockets for the NR UE correctly
connect to the proxy. We are currently receiving dl_tti
messages from the proxy.

This commit removed all the linking errors
between the NR UE and the LTE UE. This was done by
changing:
-      rrc_data_req_ue
+      rrc_data_req_nr_ue

This commit is not currently building, but I wanted
to be able to save the changes that I have added.

For some reason the htons invocation got deleted which broke
the VNF P7 interface.

Also fixed some build issues, not sure how these got onto the
develop branch to begin with.

- skipping RA procedures when MAC is disabled
- added mac_enabled flag that allows to disable RA and TA at UE from CL

- moved configuration of UE parameters to set_options function
- removed redundant loop over CCs

- removed redundant initialisation of variables
- introduced two "RF helpers" function that are replacing shared code in the sync routines
- added a new .c file and updated the cmakelists and .h files

- got rid of global variable fp
- code cleanup, removed redundant and unused code
- removed unused command line options and variables
- grouped command line setting in set_options function

- this reflects the implementation of IF and IF offset in the gNB RU
- the RF frequencies are set at HW level while the target frequencies are
  stored in fp, therefore the values stored in fp should not be changed
  after sync as only the tx/rx freq is updated
- removed overwritten dl/ul carrier frequencies in fp after sync
- removed redundant set of tx/rx freq in ue_synch (done in init_openair0)
- removed irrelevant set of dl/ul carrier freq in get_options

This commit contains work done by Eurecom and by Benetel.