Update the llfs documentation

project/Core/Inc/llfs.h

@@ -72,7 +72,7 @@ llfs_file_t* llfs_file_open(const char* name);
  *
  * @param[in, out] mem A pointer to a void* that is used internally to keep track of the current file
  * @param[in] filter  A string with file extension to filter out. (e.g. "*.txt" or "*.png")
- * @return The next file in the filesystem or NULL if there are no more files
+ * @return The next file in the filesystem or NULL if there are no more files @ref llfs_file_t
  */
 llfs_file_t* llfs_next_file(void** mem, char* filter);