Sort out some header dependencies

Marlin/planner.h

@@ -34,21 +34,12 @@
 
 #include "types.h"
 #include "enum.h"
-#include "MarlinConfig.h"
+#include "Marlin.h"
 
 #if HAS_ABL
   #include "vector_3.h"
 #endif
 
-class Planner;
-extern Planner planner;
-
-#if IS_KINEMATIC
-  // for inline buffer_line_kinematic
-  extern float delta[ABC];
-  void inverse_kinematics(const float logical[XYZ]);
-#endif
-
 /**
  * struct block_t
  *
@@ -402,4 +393,6 @@ class Planner {
 
 };
 
+extern Planner planner;
+
 #endif // PLANNER_H