FROMGIT: drm/virtio: implement blob resources: report blob mem to userspace

The stride field has never been used, so repurpose it to be
"blob_mem". This way, userspace can know the memory properties
of the blob if it's passed between userspace processes and
no suitable userspace API exists to transmit that knowledge.

Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-17-gurchetansingh@chromium.org


Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit 4429b5de01ad974219ca81a98f152c53c3d34f9b
 git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

 master)

BUG=b:171715474
TEST=compile

Change-Id: I4ffaa3cdf63417b3f351d267e16ad6574a3744d3
Signed-off-by: Guenter Roeck <groeck@chromium.org>
(cherry picked from commit 0deca9f136957d7d49977a62ed95136c8a9ee4cb)