Fix typo

include/git2/diff.h

@@ -853,7 +853,7 @@ typedef enum {
  * iteration and cause this return `GIT_EUSER`.
  *
  * @param diff A git_diff generated by one of the above functions.
- * @param format A git_diff_forrmat_t value to pick the text format.
+ * @param format A git_diff_format_t value to pick the text format.
  * @param print_cb Callback to make per line of diff text.
  * @param payload Reference pointer that will be passed to your callback.
  * @return 0 on success, GIT_EUSER on non-zero callback, or error code