Revert "[MDEV-7978] add show create user"

Appoligies, had a dirty branch before pushing:

This reverts commit 053653a.

This reverts commit 0ff8978.

This reverts commit 85b0859.

This reverts commit f3f45e4.

This reverts commit a470b35.

This reverts commit f8b8d20.

This reverts commit 6b6f066.

This reverts commit a701e9e.

This reverts commit c169838.

Author: grooverdan