Merge pull request #313 from jayzakk/lgt8-support

add support for LGT8F cpu

Adafruit_SPITFT.cpp

@@ -40,6 +40,13 @@
 #if defined(__AVR_XMEGA__) // only tested with __AVR_ATmega4809__
 #define AVR_WRITESPI(x)                                                        \
   for (SPI0_DATA = (x); (!(SPI0_INTFLAGS & _BV(SPI_IF_bp)));)
+#elif defined(__LGT8F__)
+#define AVR_WRITESPI(x)                                                        \
+  SPDR = (x);                                                                  \
+  asm volatile("nop");                                                         \
+  while ((SPFR & _BV(RDEMPT)))                                                 \
+    ;                                                                          \
+  SPFR = _BV(RDEMPT) | _BV(WREMPT)
 #else
 #define AVR_WRITESPI(x) for (SPDR = (x); (!(SPSR & _BV(SPIF)));)
 #endif