remove several unused files
remove mem_block_t that is never used in a different way than a simple heap buffer
move up IP address type and remove duplications of the same struct declaration
The RLC tests were not compiling because of the include of
openair2/RRC/NR/rrc_gNB_radio_bearers.h
by
openair2/LAYER2/nr_rlc/nr_rlc_entity.h
which does not seem correct/necessary to start with.
The only thing needed by nr_rlc_entity.h from rrc_gNB_radio_bearers.h
is MAX_DRBS_PER_UE which can be defined in common/platform_constants.h
like NGAP_MAX_PDU_SESSION.
Laurent THOMAS