board:espino:variant: rename button macro (naming coherence)

Author: d-a-v

variants/espino/pins_arduino.h

@@ -38,12 +38,7 @@ static const uint8_t SCL = PIN_WIRE_SCL;
 static const uint8_t LED_BUILTIN_R = 2;
 static const uint8_t LED_BUILTIN_G = 4;
 static const uint8_t LED_BUILTIN_B = 5;
+static const uint8_t BUTTON_BUILTIN = 0;
 
-/*
-static const uint8_t BUILTIN_LEDR = 2;
-static const uint8_t BUILTIN_LEDG = 4;
-static const uint8_t BUILTIN_LEDB = 5;
-static const uint8_t BUILTIN_BUTTON = 0;
-*/
 
 #endif /* Pins_Arduino_h */