Summary:
Remove the util functions in options_util.h that have previously been marked deprecated.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/11126

Test Plan: `make check`

Reviewed By: ltamasi

Differential Revision: D42757496

Pulled By: jowlyzhang

fbshipit-source-id: 2a138a3c207d0e0e0bbb4d99548cf2cadb44bcfb