Move flow_percentage to Planner

Marlin/src/gcode/config/M221.cpp

@@ -21,7 +21,7 @@
  */
 
 #include "../gcode.h"
-#include "../../Marlin.h"
+#include "../../module/planner.h"
 
 /**
  * M221: Set extrusion percentage (M221 T0 S95)
@@ -29,5 +29,5 @@
 void GcodeSuite::M221() {
   if (get_target_extruder_from_command()) return;
   if (parser.seenval('S'))
-    flow_percentage[target_extruder] = parser.value_int();
+    planner.flow_percentage[target_extruder] = parser.value_int();
 }