Code cleanup and documentation update

.gitlab-ci.yml

doc/NR_NFAPI_archi.md

executables/nr-gnb.c

nfapi/nrNFAPI.md

nfapi/oai_integration/nfapi_pnf.c

nfapi/oai_integration/nfapi_pnf.h

nfapi/oai_integration/nfapi_vnf.c

nfapi/oai_integration/nfapi_vnf.h

nfapi/open-nFAPI/nfapi/public_inc/nfapi_nr_interface_scf.h

nfapi/open-nFAPI/nfapi/src/nfapi_p7.c

nfapi/open-nFAPI/pnf/inc/pnf_p7.h

nfapi/open-nFAPI/pnf/src/pnf_p7.c

nfapi/open-nFAPI/pnf/src/pnf_p7_interface.c

nfapi/open-nFAPI/vnf/src/vnf_p7.c

nfapi/open-nFAPI/vnf/src/vnf_p7_interface.c

openair1/PHY/LTE_UE_TRANSPORT/dlsch_decoding.c

openair1/PHY/NR_TRANSPORT/nr_dci_tools.c

openair1/PHY/NR_TRANSPORT/nr_dlsch_coding.c

openair1/PHY/NR_TRANSPORT/nr_ulsch_decoding.c

openair1/PHY/NR_TRANSPORT/pucch_rx.c