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_display.c b/drivers/gpu/drm/i915/intel_display.c
index 8905f83..3cf284f 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9819,7 +9819,7 @@
 
 	if (!drmmode_obj) {
 		DRM_ERROR("no such CRTC id\n");
-		return -EINVAL;
+		return -ENOENT;
 	}
 
 	crtc = to_intel_crtc(obj_to_crtc(drmmode_obj));