crypto: qat - add shutdown handler to qat_4xxx

crypto: qat - add shutdown handler to qat_4xxx

During a warm reset via kexec, the system bypasses the driver removal
sequence, meaning that the remove() callback is not invoked.
If a QAT device is not shutdown properly, the device driver will fail to
load in a newly rebooted kernel.

This might result in output like the following after the kexec reboot:

    4xxx 0000:01:00.0: Failed to power up the device
    4xxx 0000:01:00.0: Failed to initialize device
    4xxx 0000:01:00.0: Resetting device qat_dev0
    4xxx 0000:01:00.0: probe with driver 4xxx failed with error -14

Implement the shutdown() handler that hooks into the reboot notifier
list. This brings down the QAT device and ensures it is shut down
properly.

Cc: <stable@vger.kernel.org>
Fixes: 8c8268166e83 ("crypto: qat - add qat_4xxx driver")
Link: https://lore.kernel.org/all/Z-DGQrhRj9niR9iZ@gondor.apana.org.au/
Reported-by: Randy Wright <rwright@hpe.com>
Closes: https://issues.redhat.com/browse/RHEL-84366
Reviewed-by: Ahsan Atta <ahsan.atta@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>