Add error notify method to report a fatal error event to all the
subsystems registered. In addition expose an API,
adf_notify_fatal_error(), that allows to trigger a fatal error
notification asynchronously in the context of a workqueue.

This will be invoked when a fatal error is detected by the ISR or
through Heartbeat.
Signed-off-by: Furong Zhou <furong.zhou@intel.com>
Reviewed-by: Ahsan Atta <ahsan.atta@intel.com>
Reviewed-by: Markas Rapoportas <markas.rapoportas@intel.com>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Mun Chun Yep <mun.chun.yep@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>