Staging: ipack: check the device ID space CRC.

We check the CRC and store the result of the check in struct ipac_device.
A warning is emitted if the check fails.  However we leave it to the
IPack module device to refuse to initialize due to a bad CRC.  I have seen
otherwise good modules with bad CRCs.

Signed-off-by: Jens Taprogge <jens.taprogge@taprogge.org>
Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>