fsi: occ: Log error for checksum failure

Log an error if the response checksum doesn't match the
calculated checksum.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20210209171235.20624-3-eajames@linux.ibm.com


Signed-off-by: Joel Stanley <joel@jms.id.au>