gralloc: use a struct for imported handle info

"Prefer to use a struct instead of a pair or a tuple
whenever the elements can have meaningful names."

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

Change-Id: I688267a4c40f0260476029c0d70bc8bb19943e21
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/3481955
Reviewed-by: Yiwei Zhang <zzyiwei@chromium.org>
Tested-by: Jason Macnak <natsu@google.com>
Commit-Queue: Jason Macnak <natsu@google.com>
2 files changed