Reduce math library code size by 3.4KB (#21575)

Marlin/src/lcd/extui/lib/ftdi_eve_touch_ui/ftdi_eve_lib/extended/adjuster_widget.cpp

@@ -32,7 +32,7 @@
 namespace FTDI {
   void draw_adjuster_value(CommandProcessor& cmd, int16_t x, int16_t y, int16_t w, int16_t h, float value, progmem_str units, int8_t width, uint8_t precision) {
     char str[width + precision + 10 + (units ? strlen_P((const char*) units) : 0)];
-    if (isnan(value))
+    if (ISNAN(value))
       strcpy_P(str, PSTR("-"));
     else
       dtostrf(value, width, precision, str);

Marlin/src/lcd/extui/lib/ftdi_eve_touch_ui/screens/bed_mesh_base.cpp

@@ -31,7 +31,7 @@ void BedMeshBase::_drawMesh(CommandProcessor &cmd, int16_t x, int16_t y, int16_t
   constexpr uint8_t cols = GRID_MAX_POINTS_X;
 
   #define VALUE(X,Y)  (func ? func(X,Y,data) : 0)
-  #define ISVAL(X,Y)  (func ? !isnan(VALUE(X,Y)) : true)
+  #define ISVAL(X,Y)  (func ? !ISNAN(VALUE(X,Y)) : true)
   #define HEIGHT(X,Y) (ISVAL(X,Y) ? (VALUE(X,Y) - val_min) * scale_z : 0)
 
   // Compute the mean, min and max for the points

Marlin/src/lcd/extui/lib/ftdi_eve_touch_ui/screens/bed_mesh_edit_screen.cpp

@@ -70,7 +70,7 @@ void BedMeshEditScreen::onEntry() {
 
 float BedMeshEditScreen::getHighlightedValue() {
   const float val = ExtUI::getMeshPoint(mydata.highlight);
-  return (isnan(val) ? 0 : val) + mydata.zAdjustment;
+  return (ISNAN(val) ? 0 : val) + mydata.zAdjustment;
 }
 
 void BedMeshEditScreen::setHighlightedValue(float value) {

Marlin/src/lcd/extui/ui_api.cpp

@@ -421,7 +421,7 @@ namespace ExtUI {
         #if AXIS_IS_TMC(Z2)
           case Z2: return stepperZ2.getMilliamps();
         #endif
-        default: return NAN;
+        default: return MFNAN;
       };
     }
 
@@ -451,7 +451,7 @@ namespace ExtUI {
         #if AXIS_IS_TMC(E7)
           case E7: return stepperE7.getMilliamps();
         #endif
-        default: return NAN;
+        default: return MFNAN;
       };
     }