feat(api-demo): add test function

hw-tests/api-demo/api.h

@@ -18,4 +18,7 @@ typedef struct {
 #define API_LED 0xc0ffee
 API(API_LED, void api_set_led(uint8_t led, led_color_t color));
 
+#define API_TEST 0xdeadc0de
+API(API_TEST, void api_test(char test0, short test1, int test2, long test3));
+
 #endif /* _API_H */

hw-tests/api-demo/core1-dispatcher.c

@@ -25,6 +25,12 @@ void api_set_led(uint8_t led, led_color_t color)
 	leds_set(led, color.red, color.green, color.blue);
 }
 
+void api_test(char test0, short test1, int test2, long test3)
+{
+	printf ("test0: %x, test1: %x, test2: %x, test3: %x\n",
+			test0, test1, test2, test3);
+}
+
 int main(void)
 {
 	api_init(NULL);
@@ -34,6 +40,7 @@ int main(void)
                 TMR_Delay(MXC_TMR1, MSEC(100), 0);
 	}
 
+
 #if 0
 	// Enable rxev on core1
 	MXC_GCR->evten |= 0x20;