pcUtil Fix parser overflow when querying power modes.

Because the response buffer was too short, querying power modes
overflow and return stack junk (usually zero) instead of giving
the actual power mode.

See: krontech/chronos-cam-app#137

src/pcUtil/comms.c

@@ -91,7 +91,7 @@ BOOL setPowerupMode(uint8 mode)
 
 BOOL getPowerupMode(uint8 * mode)
 {
-	uint8 response[1];
+	uint8 response[2];
 	uint16 length;
 	txByteMessage(COM_CMD_GET_POWERUP_MODE);