Add O-RAN compliant antenna muting for energy saving

Implements MPLANE-TRX-CONTROL feature from O-RAN WG4:
- nr_antenna_state: TX/RX antenna bitmask management
- nr_antenna_control: TCP control interface on port 9999
- Integrated into nr_feptx (TX) and nr_fep (RX) paths
- Blanks transmission/reception for muted antennas

Commands: MUTE TX/RX <id>, UNMUTE TX/RX <id>, STATUS, STATS

CMakeLists.txt

@@ -945,6 +945,8 @@ set(PHY_SRC_UE
   ${OPENAIR1_DIR}/PHY/NR_TRANSPORT/nr_prach.c
   ${OPENAIR1_DIR}/PHY/NR_TRANSPORT/nr_ulsch_llr_computation.c
   ${OPENAIR1_DIR}/PHY/NR_TRANSPORT/nr_ulsch_demodulation.c
+  ${OPENAIR1_DIR}/PHY/NR_TRANSPORT/nr_antenna_state.c
+  ${OPENAIR1_DIR}/PHY/NR_TRANSPORT/nr_antenna_control.c
   ${OPENAIR1_DIR}/PHY/NR_REFSIG/ul_ref_seq_nr.c
   ${OPENAIR1_DIR}/PHY/NR_REFSIG/nr_dmrs_rx.c
   ${OPENAIR1_DIR}/PHY/NR_REFSIG/nr_gen_mod_table.c