revert IS_PIN_ANALOG

Author: hathach

libraries/Firmata/Boards.h

@@ -786,7 +786,8 @@ writePort(port, value, bitmask):  Write an 8 bit port.
 #define TOTAL_PINS              32
 #define VERSION_BLINK_PIN       LED_BUILTIN
 #define IS_PIN_DIGITAL(p)       ((p) >= 2 && (p) < TOTAL_PINS)
-#define IS_PIN_ANALOG(p)        ( (2 <= (p) && (p) <= 5) || (28 <= (p) && (p) <= 31) )
+#define IS_PIN_ANALOG(p)        ((p) == PIN_A0 || (p) == PIN_A1 || (p) == PIN_A2  || (p) == PIN_A3 || \
+                                 (p) == PIN_A4 || (p) == PIN_A5 || (p) == PIN_A6  || (p) == PIN_A7)
 #define IS_PIN_PWM(p)           digitalPinHasPWM(p)
 #define IS_PIN_SERVO(p)         IS_PIN_DIGITAL(p)
 #define IS_PIN_I2C(p)           ((p) == PIN_WIRE_SDA || (p) == PIN_WIRE_SCL)