drm: qxl: ensure surf.data is ininitialized

The object surf is not fully initialized and the uninitialized
field surf.data is being copied by the call to qxl_bo_create
via the call to qxl_gem_object_create. Set surf.data to zero
to ensure garbage data from the stack is not being copied.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: f64122c ("drm: add new QXL driver. (v1.4)")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210608161313.161922-1-colin.king@canonical.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

drivers/gpu/drm/qxl/qxl_dumb.c

@@ -58,6 +58,8 @@ int qxl_mode_dumb_create(struct drm_file *file_priv,
 	surf.height = args->height;
 	surf.stride = pitch;
 	surf.format = format;
+	surf.data = 0;
+
 	r = qxl_gem_object_create_with_handle(qdev, file_priv,
 					      QXL_GEM_DOMAIN_CPU,
 					      args->size, &surf, &qobj,