New function to modify fifo overwritability

src/common/tusb_fifo.h

@@ -76,6 +76,7 @@ typedef struct
       .overwritable = _overwritable,         \
   }
 
+bool tu_fifo_change_mode(tu_fifo_t *f, bool overwritable);
 bool tu_fifo_clear(tu_fifo_t *f);
 bool tu_fifo_config(tu_fifo_t *f, void* buffer, uint16_t depth, uint16_t item_size, bool overwritable);