drm/qxl: drop use of drmP.h

Drop use of the deprecated drmP.h header file.
While touching the files divided includes in blocks,
and when needed sort the blocks.
Fix fallout.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Emil Velikov <emil.velikov@collabora.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: virtualization@lists.linux-foundation.org
Cc: spice-devel@lists.freedesktop.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190630061922.7254-10-sam@ravnborg.org