drm/xe: Fix the gem shrinker name

The xe buffer object shrinker name is visible in the
<debugfs>/shrinker directory and most if not all other shinkers
follow a naming convention that looks like
<subsystem>-<driver>_<objects>:<unique>
Follow the same convention for xe, changing the name to
drm-xe_gem:<unique>.

Other shrinkers typically use the device node for <unique> but
since drm drivers typically don't have a single unique device-
node, instead use the unique name in the drm device.

Fixes: 00c8efc3180f ("drm/xe: Add a shrinker for xe bos")
Cc: Matthew Brost <[e-mail]>
Signed-off-by: Thomas Hellström <[e-mail]>
Reviewed-by: Francois Dugast <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/gpu/drm/xe/xe_shrinker.c

···
 	if (!shrinker)
 		return ERR_PTR(-ENOMEM);
 
-	shrinker->shrink = shrinker_alloc(0, "xe system shrinker");
+	shrinker->shrink = shrinker_alloc(0, "drm-xe_gem:%s", xe->drm.unique);
 	if (!shrinker->shrink) {
 		kfree(shrinker);
 		return ERR_PTR(-ENOMEM);