Fix more compiler warnings

teensy3/core_pins.h

 #elif defined(__MKL26Z64__)
 #define CORE_NUM_TOTAL_PINS     27
 #define CORE_NUM_DIGITAL        27
-#define CORE_NUM_INTERRUPT      18
+#define CORE_NUM_INTERRUPT      24  // really only 18, but 6 "holes"
 #define CORE_NUM_ANALOG         13
 #define CORE_NUM_PWM            10
 #endif

teensy3/usb_joystick.h

 		if (!manual_mode) usb_joystick_send();
 	}
         inline void hat(int dir) {
-                uint32_t val;
+                uint32_t val = 0;
                 if (dir < 0) val = 15;
                 else if (dir < 23) val = 0;
                 else if (dir < 68) val = 1;