Fix build

src/TTGO_T-Beam_LoRa_APRS.ino

@@ -181,8 +181,8 @@ float average_speed[5] = {0,0,0,0,0}, average_speed_final=0;
 
 float old_course = 0, new_course = 0;
 int point_avg_speed = 0, point_avg_course = 0;
-ulong min_time_to_nextTX=SB_min_interval;      // minimum time period between TX = 60000ms = 60secs = 1min
-ulong max_time_to_nextTX= SB_max_interval;
+ulong min_time_to_nextTX=sb_min_interval;      // minimum time period between TX = 60000ms = 60secs = 1min
+ulong max_time_to_nextTX= sb_max_interval;
 
 ulong nextTX=60000L;                  // preset time period between TX = 60000ms = 60secs = 1min
 ulong time_to_refresh = 0;