Ticket 48989 - Improve counter overflow fix
Fix Description:
* load should only be a load, no cmp xchg
* set can be a store_n, which still is atomic. We don't need cmp xchg
* Add a cmocka test case of the values
* remove the sunos asm
* remove the x86 asm
https://pagure.io/389-ds-base/issue/48989
Author: wibrown
Review by: mreynolds (Thanks!)