Update the PFVF logic to handle restart and recovery. This adds the
following functions:

  * adf_pf2vf_notify_fatal_error(): allows the PF to notify VFs that the
    device detected a fatal error and requires a reset. This sends to
    VF the event `ADF_PF2VF_MSGTYPE_FATAL_ERROR`.
  * adf_pf2vf_wait_for_restarting_complete(): allows the PF to wait for
    `ADF_VF2PF_MSGTYPE_RESTARTING_COMPLETE` events from active VFs
    before proceeding with a reset.
  * adf_pf2vf_notify_restarted(): enables the PF to notify VFs with
    an `ADF_PF2VF_MSGTYPE_RESTARTED` event after recovery, indicating that
    the device is back to normal. This prompts VF drivers switch back to
    use the accelerator for workload processing.

These changes improve the communication and synchronization between PF
and VF drivers during system restart and recovery processes.
Signed-off-by: Mun Chun Yep <mun.chun.yep@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: Herbert Xu <herbert@gondor.apana.org.au>