Fix outdated comment for IndexInfo
Commit
78416235713 removed the ii_OpclassOptions field, but the
comment was not updated.
Author: Japin Li <japinli@hotmail.com>
Reviewed-by: Richard Guo <guofenglinux@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/ME0P300MB04453E6C7EA635F0ECF41BFCB6832%40ME0P300MB0445.AUSP300.PROD.OUTLOOK.COM