s390/chsc: fix ioctl CHSC_INFO_CU command

Via CHSC_INFO_CU we ought to provide userspace with control unit
configuration data. Due to an erroneous request code we trigger the
wrong chsc command. Fix this copy and paste error.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>