Note which task is using the entity and only kill it if the last user of
the entity is killed. This should prevent problems when entities are leaked to
child processes.

v2: add missing kernel doc
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NAndrey Grodzovsky <andrey.grodzovsky@amd.com>
Acked-by: NNayan Deshmukh <nayan26deshmukh@gmail.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>