Merge pull request #23 from zsa/fix/avr_gcc_compiler

Fix AVR GCC 8.x compiler error

changelog.md

@@ -5,6 +5,7 @@
 04-16-2019 - Fix info.json for Ergodox EZ   
 04-16-2019 - Add support for WS2812 based RGB Matrix   
 04-18-2019 - Fix Eager Per Row Debouncing bug  
+04-22-2019 - Make sure NOBITS is set on reset_key   
 04-22-2019 - Improve Mousekey constant speed mode  
 04-22-2019 - Add new reactive modes (wide, cross, nexus) for RGB Matrix  
 04-22-2019 - OLED Driver Features  

tmk_core/common/avr/bootloader.c

@@ -70,7 +70,7 @@
  * http://www.fourwalledcubicle.com/files/LUFA/Doc/120730/html/_page__software_bootloader_start.html
  */
 #define BOOTLOADER_RESET_KEY 0xB007B007
-uint32_t reset_key  __attribute__ ((section (".noinit")));
+uint32_t reset_key  __attribute__ ((section (".noinit,\"aw\",@nobits;")));
 
 /** \brief initialize MCU status by watchdog reset
  *