zink: Added support for MacOS MoltenVK APIs.

zink: Added support for MacOS MoltenVK APIs.

Detects the MoltenVK layer and extension.
If present, get the ext function pointers and use to enable full swizzeling suport.
Fixes issues with Swizzling behaviour fro MoltenVk is disabled by default and needed to be enable via this API.

This also supplied the ground work to allow IOSurfaces to be used later for surface passing.

Reviewed-By: Mike Blumenkrantz <michael.blumenkrantz@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7383>