Save some tiny amounts of RAM

- use `-D WLED_SAVE_RAM`

wled00/FX.h

@@ -720,6 +720,9 @@ class WS2812FX {  // 96 bytes
 #ifndef WLED_DISABLE_2D
       panels(1),
 #endif
+      autoSegments(false),
+      correctWB(false),
+      cctFromRgb(false),
       // semi-private (just obscured) used in effect functions through macros
       _colors_t{0,0,0},
       _virtualSegmentLength(0),
@@ -908,6 +911,12 @@ class WS2812FX {  // 96 bytes
     void loadCustomPalettes(void); // loads custom palettes from JSON
     std::vector<CRGBPalette16> customPalettes; // TODO: move custom palettes out of WS2812FX class
 
+    struct {
+      bool autoSegments : 1;
+      bool correctWB    : 1;
+      bool cctFromRgb   : 1;
+    };
+
     // using public variables to reduce code size increase due to inline function getSegment() (with bounds checking)
     // and color transitions
     uint32_t _colors_t[3]; // color used for effect (includes transition)