fix run_mmc.sh script blocking cause by missing & on the rtsp server

SD_ROOT/wz_mini/run_mmc.sh

@@ -442,7 +442,7 @@ if [[ "$RTSP_LOW_RES_ENABLED" == "true" ]]; then
 fi
 
 if [[ "$RTSP_LOW_RES_ENABLED" == "true" ]] || [[ "$RTSP_HI_RES_ENABLED" == "true" ]]; then
-	LD_LIBRARY_PATH=/media/mmc/wz_mini/lib /media/mmc/wz_mini/bin/v4l2rtspserver $AUDIO_CH $AUDIO_FMT -U $RTSP_LOGIN:$RTSP_PASSWORD -P $RTSP_PORT $DEVICE1 $DEVICE2
+	LD_LIBRARY_PATH=/media/mmc/wz_mini/lib /media/mmc/wz_mini/bin/v4l2rtspserver $AUDIO_CH $AUDIO_FMT -U $RTSP_LOGIN:$RTSP_PASSWORD -P $RTSP_PORT $DEVICE1 $DEVICE2 &
 fi
 
 hostname_set