added ISR register to vPortSetupTimer() function

tests/FreeRTOS/freertos_test.c

@@ -54,9 +54,6 @@ int main( void )
 
 	printf("Starting FreeRTOS test\n");
 
-	/* register ISR */
-	register_timer_isr();
-
         my_queue = xQueueCreate(10, sizeof(int));
         
         /* Create tasks */

tests/FreeRTOS/port.c

@@ -189,6 +189,9 @@ void vPortSetupTimer(void)
 #endif
 
         volatile uint32_t timer_value;
+        
+        register_timer_isr();
+        
         timer_value = TIMER;
         // timer_value += configTICK_CLOCK_HZ / configTICK_RATE_HZ;
 	timer_value += 10000 - 620;        // timer set to 100 Hz and corrected