This fixes the build warning:
"ignoring return value of 'register_shrinker', declared with
attribute warn_unused_result [-Wunused-result]"
Signed-off-by: Roger He <Hongbo.He@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>