Make display support configurable per-target, enabled by default for

NAZE and EUSTM32F103RC.

src/main/io/display.c

@@ -22,6 +22,8 @@
 
 #include "build_config.h"
 
+#ifdef DISPLAY
+
 #include "drivers/system.h"
 #include "drivers/display_ug2864hsweg01.h"
 
@@ -70,3 +72,5 @@ void displayInit(void)
     delay(20);
     ug2864hsweg01InitI2C();
 }
+
+#endif

src/main/main.c

@@ -139,7 +139,9 @@ void init(void)
 
     initBoardAlignment(&masterConfig.boardAlignment);
 
+#ifdef DISPLAY
     displayInit();
+#endif
 
     // We have these sensors; SENSORS_SET defined in board.h depending on hardware platform
     sensorsSet(SENSORS_SET);

src/main/mw.c

@@ -432,9 +432,11 @@ void executePeriodicTasks(void)
         }
         break;
 #endif
+#ifdef DISPLAY
     case UPDATE_DISPLAY_TASK:
         updateDisplay();
         break;
+#endif
     }
 
     if (periodicTaskIndex >= PERIODIC_TASK_COUNT) {

src/main/target/EUSTM32F103RC/target.h

@@ -22,6 +22,7 @@
 #define GYRO
 #define MAG
 #define SONAR
+#define DISPLAY
 
 #define USE_USART1
 #define USE_USART2

src/main/target/NAZE/target.h

@@ -46,6 +46,7 @@
 #define LED0
 #define LED1
 #define INVERTER
+#define DISPLAY
 
 #define USE_USART1
 #define USE_USART2