L1 perf logging changes

Moved the L1 timing stats logs from stdout to nrL1_stats.log

openair2/LAYER2/NR_MAC_gNB/main.c

@@ -121,7 +121,7 @@ void dump_mac_stats(gNB_MAC_INST *gNB, char *output, int strlen)
       }
     }
   }
-  print_meas(&gNB->eNB_scheduler, "DL & UL scheduling timing stats", NULL, NULL);
+  print_meas_log(&gNB->eNB_scheduler, "DL & UL scheduling timing stats", NULL, NULL, output+stroff);
 }