Fix compile errors for using the Pixie led chipset

Author: focalintent

FastLED.cpp

@@ -220,6 +220,7 @@ void CFastLED::setMaxRefreshRate(uint16_t refresh, bool constrain) {
   }
 }
 
+extern "C" int atexit(void (* /*func*/ )()) { return 0; }
 
 #ifdef NEED_CXX_BITS
 namespace __cxxabiv1

FastLED.h

@@ -71,7 +71,10 @@ enum ESPIChipsets {
 enum ESM { SMART_MATRIX };
 enum OWS2811 { OCTOWS2811,OCTOWS2811_400 };
 
-template<uint8_t DATA_PIN, EOrder RGB_ORDER> class Pixie : public PixieController<DATA_PIN, RGB_ORDER> {};
+#ifdef HAS_PIXIE
+template<uint8_t DATA_PIN, EOrder RGB_ORDER> class PIXIE : public PixieController<DATA_PIN, RGB_ORDER> {};
+#endif
+
 #ifdef FASTLED_HAS_CLOCKLESS
 template<uint8_t DATA_PIN> class NEOPIXEL : public WS2812Controller800Khz<DATA_PIN, GRB> {};
 template<uint8_t DATA_PIN, EOrder RGB_ORDER> class TM1829 : public TM1829Controller800Khz<DATA_PIN, RGB_ORDER> {};

chipsets.h

@@ -12,9 +12,14 @@ FASTLED_NAMESPACE_BEGIN
 ///
 ///@{
 
-#if defined(ARDUINO)
+#if defined(ARDUINO) //&& defined(SoftwareSerial_h)
+
+
+#if defined(SoftwareSerial_h)
 #include "SoftwareSerial.h"
 
+#define HAS_PIXIE
+
 /// Adafruit Pixie controller class
 /// @tparam DATAPIN the pin to write data out on
 /// @tparam RGB_ORDER the RGB ordering for the led data
@@ -71,6 +76,7 @@ class PixieController : public CLEDController {
 // 	}
 // };
 #endif
+#endif
 
 ///@name Clocked chipsets - nominally SPI based these chipsets have a data and a clock line.
 ///@{