Merge remote-tracking branch 'origin/remove-unused-code' into integration_2026_w14 (!4020)

Remove a lot of unused code, defines, and config options

Remove unused header files and defines.

Slightly clean up gnb_config.c by removing all _IDX variables. Remove
these unused parameters:

- MACRLCs.[0].num_cc
- MACRLCs.[0].local_n_portc
- MACRLCs.[0].remove_n_portc
- MACRLCs.[0].remote_s_portc
- MACRLCs.[0].remote_s_portd
- L1s.[0].num_cc
- L1s.[0].local_n_portc

openair1/PHY/defs_gNB.h

@@ -358,8 +358,6 @@ typedef struct PHY_VARS_gNB_s {
   gNB_L1_proc_t proc;
   int num_RU;
   RU_t *RU_list[MAX_NUM_RU_PER_gNB];
-  /// Ethernet parameters for northbound midhaul interface
-  eth_params_t eth_params_n;
   /// Ethernet parameters for fronthaul interface
   eth_params_t eth_params;
   int rx_total_gain_dB;