Summary of changes from previous revision:
* Tests no longer bother checking for buffer writes past returned number of adapters * Tests now check returned initial `NumAdapters` to be one of known returned values * List of GPUs is now read from registry and cached in-memory in win32u (constructed in `update_display_cache_from_registry` and dropped in `clear_display_devices`) * Because `EnumAdapters2` needs only LUIDs, there are no attempts to read, parse or cache other GPU properties * `EnumAdapters2` now supports up to 34 adapters, to match Windows 11 * `EnumAdapters2` now iterates through GPUs list to obtain its results, but still uses adapters list to calculate `NumOfSources` * `EnumAdapters2` no longer allocates memory for temporary working-area adapters list, instead the passed buffer is used directly (and zeroed when error is encountered) * Rebased against Wine 9.1