f2fs: the name of a struct is wrong in a comment.

The macro SUMMARY_SIZE represents the size of the struct f2fs_summary,

instead of the size of the struct summary.
Signed-off-by: Yang Hubin <yanghb2019@lzu.edu.cn>
Signed-off-by: Qian Haolai <qianhl2023@lzu.edu.cn>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

include/linux/f2fs_fs.h

@@ -441,7 +441,7 @@ struct f2fs_sit_block {
  * ex) data_blkaddr = (block_t)(nodepage_start_address + ofs_in_node)
  */
 #define ENTRIES_IN_SUM		(F2FS_BLKSIZE / 8)
-#define	SUMMARY_SIZE		(7)	/* sizeof(struct summary) */
+#define	SUMMARY_SIZE		(7)	/* sizeof(struct f2fs_summary) */
 #define	SUM_FOOTER_SIZE		(5)	/* sizeof(struct summary_footer) */
 #define SUM_ENTRY_SIZE		(SUMMARY_SIZE * ENTRIES_IN_SUM)