gralloc: use dmabuf-heaps when available

... for reserved region / metadata as dmabuf heaps are the hot new
thing replacing ion.

Also, Android already has sepolicy in place for passing around
dmabufs (see `dmabuf_system_heap_device:chr_file` references in
system/sepolicy) while memfds require manual additions (see
aosp/1960673).

BUG=b:207388558
TEST=cvd start
TEST=vts -m VtsHalGraphicsMapperV4_0Target

Change-Id: I9acb30a10afb1f9f273ceb17dd44a9ac96da1a97
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/3449613
Reviewed-by: Roman Stratiienko <r.stratiienko@gmail.com>
Reviewed-by: Yiwei Zhang <zzyiwei@chromium.org>
Tested-by: Jason Macnak <natsu@google.com>
Commit-Queue: Jason Macnak <natsu@google.com>
2 files changed