[2.0.x] Fix undefined symbol 'g29_in_progress' (#11781)

Marlin/src/gcode/calibrate/G28.cpp

@@ -205,14 +205,15 @@ void GcodeSuite::G28(const bool always_home_all) {
   // Wait for planner moves to finish!
   planner.synchronize();
 
+  // Disable the leveling matrix before homing
+  #if HAS_LEVELING
+
     // Cancel the active G29 session
     #if ENABLED(PROBE_MANUALLY)
       extern bool g29_in_progress;
       g29_in_progress = false;
     #endif
 
-  // Disable the leveling matrix before homing
-  #if HAS_LEVELING
     #if ENABLED(RESTORE_LEVELING_AFTER_G28)
       const bool leveling_was_active = planner.leveling_active;
     #endif