🐛 Fix SENSORLESS_HOMING for 6-axis

Marlin/src/gcode/calibrate/G28.cpp

 
     #if ENABLED(SENSORLESS_HOMING)
       sensorless_t stealth_states {
-          tmc_enable_stallguard(stepperX)
-        , tmc_enable_stallguard(stepperY)
-        , false
+          LINEAR_AXIS_LIST(tmc_enable_stallguard(stepperX), tmc_enable_stallguard(stepperY), false, false, false, false)
         , false
           #if AXIS_HAS_STALLGUARD(X2)
             || tmc_enable_stallguard(stepperX2)