CL/Vulkan: Set host cached bit for HOST_PTR buffers Leads to better performance on "clEnqueueReadBuffer" operations when CL buffers are created as host-pointer based buffers. Bug: angleproject:42267018 Change-Id: I18048deea96858180b63cfad95fe33fbab7f11c9 Signed-off-by: kyongjoo.oh <kyongjoo.oh@samsung.com> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/6981096 Commit-Queue: Austin Annestrand <a.annestrand@samsung.com> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>