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

executables/nr-gnb.c

@@ -48,6 +48,7 @@
 #include "NR_PHY_INTERFACE/NR_IF_Module.h"
 #include "PHY/INIT/nr_phy_init.h"
 #include "PHY/MODULATION/nr_modulation.h"
+#include "PHY/NR_TRANSPORT/nr_antenna_control.h"
 #include "PHY/NR_TRANSPORT/nr_transport_proto.h"
 #include "PHY/TOOLS/tools_defs.h"
 #include "PHY/defs_RU.h"
@@ -403,6 +404,13 @@ void init_eNB_afterRU(void)
      */
     //init_precoding_weights(RC.gNB[inst]);
     init_gNB_Tpool(inst);
+
+    // Start O-RAN antenna control test server (port 9999)
+    // Allows runtime antenna muting for energy saving testing
+    // Connect with: nc localhost 9999
+    if (nr_antenna_control_start(&gNB->antenna_state, 9999)) {
+      LOG_I(PHY, "[ANTENNA_CTRL] Test control server started on port 9999\n");
+    }
   }
 }