venus: cache ahb backed buffer memory type bits requirement

venus: cache ahb backed buffer memory type bits requirement

To properly init buffer memory requirement for AHB, memory type bits
from dma_buf fd properties need to be masked. However, creating a test
AHB at buffer creation is too costy. This patch caches the ahb backed
buffer memory type bits at device creation time if the app is requesting
AHB extension.

Cc: 21.2 mesa-stable
Signed-off-by: Yiwei Zhang <zzyiwei@chromium.org>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/12171>