s390/sclp: Allow to request adapter reset

The SCLP event 24 "Adapter Error Notification" supports three different
action qualifier of which 'adapter reset' is currently not enabled in
the sysfs interface. However, userspace tools might want to be able
to use the reset functionality as well. Enable the 'adapter reset'
qualifier.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>