mediatek/rockchip: Use PRIu64 to print uint64_t variables

mediatek/rockchip: Use PRIu64 to print uint64_t variables

Required to build for arm64 on mediatek, and let's fix the
rockchip one, while we're at it.

BUG=b:140228960
TEST=emerge-kevin-arc64 -av arc-cros-gralloc
TEST=emerge-kukui -av arc-cros-gralloc (with ARC++ 64-bit)

Change-Id: I8e04355a4d247b44ac86963331be72495655d321
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/minigbm/+/1775949
Tested-by: Nicolas Boichat <drinkcat@chromium.org>
Auto-Submit: Nicolas Boichat <drinkcat@chromium.org>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Gurchetan Singh <gurchetansingh@chromium.org>
Commit-Queue: Nicolas Boichat <drinkcat@chromium.org>