d3d12: Cache the texture array cap requirement in encoder creation for calls to d3d12_video_create_dpb_buffer

Previously, the caps were not queried until after the first DPB buffer
was created. That causes the AOT path to be triggered even when the
device does report a requirement for texture array.

Tested-by: Benjamin Cheng <benjamin.cheng@amd.com>
Reviewed-by: Benjamin Cheng <benjamin.cheng@amd.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33824>
3 files changed