finally able to get freeRTOS run with current mouse + keyboard example

NOTES: print_greeting if is executed before the start of freeRTOS scheduler --> hardfault
- print_greeting->vsprintf->systick -> bunch of ISR --> hardfault.

printf using serial after the start of scheduler is ok though

tinyusb/common/assertion.h

@@ -76,7 +76,7 @@ extern "C"
 
   //#if ( defined CFG_PRINTF_UART || defined CFG_PRINTF_USBCDC || defined CFG_PRINTF_DEBUG )
 #if TUSB_CFG_DEBUG == 3
-  #define _PRINTF(...)	printf(__VA_ARGS__)
+  #define _PRINTF(...)	printf(__VA_ARGS__) // PRINTF
 #else
   #define _PRINTF(...)
 #endif