keyboard-fw: fix 'display' definition

reform2-keyboard-fw/oled.c

@@ -13,6 +13,7 @@
 #include <avr/pgmspace.h>
 #include "gfx/font.c"
 
+struct CharacterMatrix display;
 int oledbrt = 0;
 
 // Write command sequence.

reform2-keyboard-fw/oled.h

@@ -68,8 +68,6 @@ struct CharacterMatrix {
   bool dirty;
 };
 
-struct CharacterMatrix display;
-
 void gfx_poke(uint8_t x, uint8_t y, uint8_t c);
 void gfx_poke_str(uint8_t x, uint8_t y, char* str);
 void gfx_clear_invert(void);