drm/nouveau/kms: add Maxwell to backlight initialization

Signed-off-by: Faris Alsalama <farisbenbrahem@gmail.com>
Acked-by: Acked-by: Pierre Moreau <pierre.morrow@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drivers/gpu/drm/nouveau/nouveau_backlight.c

@@ -232,6 +232,7 @@ nouveau_backlight_init(struct drm_device *dev)
 		case NV_DEVICE_INFO_V0_TESLA:
 		case NV_DEVICE_INFO_V0_FERMI:
 		case NV_DEVICE_INFO_V0_KEPLER:
+		case NV_DEVICE_INFO_V0_MAXWELL:
 			return nv50_backlight_init(connector);
 		default:
 			break;