s390/crypto: return -EFAULT if copy_to_user() fails

s390/crypto: return -EFAULT if copy_to_user() fails

The copy_to_user() function returns the number of bytes remaining to be
copied, but we want to return -EFAULT if the copy doesn't complete.

Fixes: 0cf26ce85872 ("s390: vfio-ap: implement VFIO_DEVICE_GET_INFO ioctl")
Signed-off-by: Wang Qing <wangqing@vivo.com>
Reviewed-by: Tony Krowiak <akrowiak@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Link: https://lore.kernel.org/r/1614600502-16714-1-git-send-email-wangqing@vivo.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>