Add statements for FreeRTOS

hw/bsp/msp432e4/family.c

@@ -77,6 +77,9 @@ void board_init(void)
   SystemCoreClockUpdate();
 #if CFG_TUSB_OS == OPT_OS_NONE
   SysTick_Config(SystemCoreClock / 1000);
+#elif CFG_TUSB_OS == OPT_OS_FREERTOS
+  // If freeRTOS is used, IRQ priority is limit by max syscall ( smaller is higher )
+  NVIC_SetPriority(USB0_IRQn, configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY );
 #endif
 
   /* USR_LED1 PN1 */