CI: Remove USRP mgmt_addr from LTE-2x2 conf files

The "mgmt_addr" parameter is not required for USRP N310 initialization. The
critical parameter for successful operation is the "addr", which specifies
the IP address of the SFP port used for data transfer.

Including both "mgmt_addr" and "addr" can lead to initialization failures if
one of the specified addresses is unavailable. Since the "mgmt_addr" is
unnecessary for this context, it has been removed to avoid potential conflicts
and simplify the configuration.

ci-scripts/conf_files/enb.band38.lte_2x2.100prb.usrpn310.conf

@@ -230,7 +230,7 @@ RUs = (
          max_pdschReferenceSignalPower = -27;
          max_rxgain                    = 75;
          eNB_instances  = [0];
-         sdr_addrs      = "mgmt_addr=172.21.19.13,addr=192.168.80.250";
+         sdr_addrs      = "addr=192.168.80.250";
 
     }
 );  

ci-scripts/conf_files/enb.band38.lte_2x2_tm2.100prb.usrpn310.conf

@@ -230,7 +230,7 @@ RUs = (
          max_pdschReferenceSignalPower = -27;
          max_rxgain                    = 75;
          eNB_instances  = [0];
-         sdr_addrs      = "mgmt_addr=172.21.19.13,addr=192.168.80.250";
+         sdr_addrs      = "addr=192.168.80.250";
 
     }
 );  

ci-scripts/conf_files/enb.band38.nsa_2x2.100prb.usrpn310.conf

@@ -230,7 +230,7 @@ RUs = (
          max_pdschReferenceSignalPower = -27;
          max_rxgain                    = 75;
          eNB_instances  = [0];
-         sdr_addrs      = "mgmt_addr=172.21.19.13,addr=192.168.80.250";
+         sdr_addrs      = "addr=192.168.80.250";
 
     }
 );