crypto: qat - ensure correct order in VF restarting handler

In the process of sending the ADF_PF2VF_MSGTYPE_RESTARTING message to
Virtual Functions (VFs), the Physical Function (PF) should set the
`vf->restarting` flag to true before dispatching the message.
This change is necessary to prevent a race condition where the handling
of the ADF_VF2PF_MSGTYPE_RESTARTING_COMPLETE message (which sets the
`vf->restarting` flag to false) runs immediately after the message is sent,
but before the flag is set to true.

Set the `vf->restarting` to true before sending the message
ADF_PF2VF_MSGTYPE_RESTARTING, if supported by the version of the
protocol and if the VF is started.

Fixes: ec26f8e6 ("crypto: qat - update PFVF protocol for recovery")
Signed-off-by: Michal Witwicki <michal.witwicki@intel.com>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>