add OFFSET_CALIBRATION flag to DSmobile 600

backend/genesys_devices.c

@@ -1529,6 +1529,7 @@ static Genesys_Model pentax_dsmobile_600_model = {
   MOTOR_DSMOBILE_600,
   GENESYS_FLAG_LAZY_INIT 	/* Which flags are needed for this scanner? */
     | GENESYS_FLAG_SKIP_WARMUP
+    | GENESYS_FLAG_OFFSET_CALIBRATION
     | GENESYS_FLAG_DARK_CALIBRATION,
   GENESYS_HAS_SCAN_SW | GENESYS_HAS_PAGE_LOADED_SW | GENESYS_HAS_CALIBRATE,
   100,