FROMGIT: drm/virtio: implement blob resources: hypercall interface

This implements the blob hypercall interface.

Signed-off-by: Gurchetan Singh <gurchetansingh@chromium.org>
Acked-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20200924003214.662-13-gurchetansingh@chromium.org


Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit c7a6ac4f60bc54a0a45de76a3a258685024c9293
 git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git

 master)

BUG=b:171715474
TEST=compile

Change-Id: Ic7fa11ffe8db4eaadb9806119714caf07d6f2c8c
Signed-off-by: Guenter Roeck <groeck@chromium.org>
(cherry picked from commit c2b5810c2ca07a6bb3fda852e7ca01a9487d458c)