add synchronous (blocking) support for usbh control transfer

- add synchronous version of all get descriptor API
- update bare example to use sync API for string descriptor
- change order of index, language_id in tuh_descriptor_get_string() to
match similar API of libusb
- add index to tuh_descriptor_get_hid_report()

src/tusb_option.h

@@ -285,7 +285,7 @@
   #define CFG_TUSB_OS_INC_PATH
 #endif
 
-// mutex is only needed for RTOS
+// mutex is only needed for RTOS TODO also required with multiple core MCUs
 #define TUSB_OPT_MUTEX    (CFG_TUSB_OS != OPT_OS_NONE)
 
 //--------------------------------------------------------------------