Added the following folder:
- ../openair1/PHY/NR_ESTIMATION/

Added the following file to CMakelists.txt:
- ../openair1/PHY/NR_ESTIMATION/nr_ul_channel_estimation.c

Added the following functions:
- nr_pusch_dmrs_rx
- nr_gold_pusch
- nr_ulsch_channel_level
- nr_ulsch_channel_compensation
- nr_ulsch_scale_channel is commented out (I think only used for downlink)

Changes from Khalid Ahmed Mahmoud Mohamed:
- nr_pusch_channel_estimation is used
- nr_ulsch_scale_channel is used
- nr_ulsch_channel_level is used
- nr_ulsch_channel_compensation is used
- multiple logging options for channel and signal magnitude

Added the following structs and enums in "defs_gNB.h"
- NR_UL_gNB_HARQ_t
- NR_gNB_ULSCH_t
- NR_SCH_status_t

added the following structs in "nfapi_nr_interface.h"
- nfapi_nr_ul_config_ulsch_pdu
- nfapi_nr_ul_config_ulsch_pdu_rel15_t
- nfapi_nr_ul_srs_config_t
- nr_pusch_freq_hopping_t

added nr_ulsch.h for the ulsch decoding function declarations
- free_gNB_ulsch
- new_gNB_ulsch
- nr_ulsch_decoding

added nr_ulsch_decoding.c for the implementation of the ulsch decoding functions
- free_gNB_ulsch
- new_gNB_ulsch
- nr_ulsch_decoding

BWP information in NFAPI gNB/UE
dci encoding / decoding integrated
DCI decoding still fails