drm/i915: Return -ENOENT when a mode object can't be found

Let's be a bit more consistent with our error values.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
index 8afaad6..07b13dc 100644
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -955,7 +955,7 @@
 
 	obj = drm_mode_object_find(dev, set->plane_id, DRM_MODE_OBJECT_PLANE);
 	if (!obj) {
-		ret = -EINVAL;
+		ret = -ENOENT;
 		goto out_unlock;
 	}
 
@@ -984,7 +984,7 @@
 
 	obj = drm_mode_object_find(dev, get->plane_id, DRM_MODE_OBJECT_PLANE);
 	if (!obj) {
-		ret = -EINVAL;
+		ret = -ENOENT;
 		goto out_unlock;
 	}