- New Data Structure to store PTRS RE's is removed
- LLR's are calculated at the end symbol for whole slot

FEATURE STATEMENT:
- Introduce linear phase error noise model in Uplink at UE
- Perform common phase error (CPE) estimation and compensation at gNB

SOLUTION:
- A linear phase shift model is introduced in simulation.
- PTRS symbols are used to perform estimation of CPE from DMRS compensated signal
- The estimated values are interpolated in time domain and signal is compensated for the CPE.
- PTRS processing is done in Frequency Domain for each symbol in a slot and
  LLR's are calculated for each symbol accordingly.

IMPLEMENTATION:
* sim.h/channle_sim.c
- Linear Phase Noise Generation model definition.
* nr_ul_channel_estimation.c/nr_ul_estimation.h
- CPE estimation from PTRS and DMRS compensated signal.
* nr_dmrs_rx.c/nr_refsig.h
- Regenerate PTRS symbols at gNB.
* nr_ulsch_demodulation.c
- Removed old PTRS processing code and move to a common PTRS processing function
* defs_gNB.h/init.c
- New PTRS variables definition and initialization
* nr_ulsch_ue.c
- Corrected PTRS parameter to get new PTRS symbols for each OFDM symbol

TESTING
* ulsim.c
- Added Phase noise, Enable PTRS signal and verified the output.

VERIFICATION
- The LLR are rotated back with estimated CPE and no error is observed in scrambling/decoding

pucch receiver for format 0 reworked without floating point and no generation of sequences for each decoding attempt, SR detection integrated

added scheduling of PRACH RX procedures in gNB and RU entities. Initialization of prach sequences added to nr_init.c

added FAPI interfaces int gNB prach receiver functions (rx_nr_prach,rx_nr_prach_ru) and in indication to MAC.

Testing of NR PDCCH/PDSCH with RRC Configuration. added RRC configuration to NR UE. Updates to UE DCI procedures (moved to MAC) and updates to FAPI interfaces for UE. nr_dlsim is functional, added profiling information for gNB TX.