Missing documentation on zesInit usage

[bellekal]

Description
https://spec.oneapi.io/level-zero/latest/sysman/api.html - Spec says zesInit will only initialize sysman. To initialize other functions, call zeInit. But inorder for both to work, it should be clearly documented that Sysman is not initialized before using zeInit + ZES_ENABLE_SYSMAN=1 i.e Either zeInit + zesInit both can be used only if ZES_ENABLE_SYSMAN is not set.

Also, zesDriverGet, zesDeviceGet and few newer APIs only work when initialized using zesInit and won't work when initialized with zeInit + ZES_ENABLE_SYSMAN.