Make the function name more explicit and a better match for
GetDisplayName.

Change NAME to CONFIG_NAME while I'm at it.

Bug: https://bugs.dolphin-emu.org/issues/13404

On macOS 13.6 / Intel HD 5000, Dolphin crashes with this message:

> -[MTLIGAccelDevice setShouldMaximizeConcurrentCompilation:]: unrecognized selector

This should be available on all macOS 13.3+ systems – but when using OCLP drivers,
some devices use an older version of Metal.framework, which doesn't expose the selector.

This concerns Intel Ivy Bridge, Haswell and Nvidia Kepler when using OCLP on macOS 13.3
or newer.
(See
https://github.com/dortania/OpenCore-Legacy-Patcher/blob/34676702f494a2a789c514cc76dba19b8b7206b1/docs/PATCHEXPLAIN.md?plain=1#L354C1-L354C83)

As the behavior is an optional optimization anyway, perform a dynamic
detection to avoid crashing if the feature is not available.

VideoBackends:Metal: Enable shouldMaximizeConcurrentCompilation when available

The whole ownership model was getting a bit of a mess, with a some
of special cases to deal with. And I'm planning to make it even more
complex in the future.
So here is some upfront work to convert it over to reference counted
pointers.