s390/sclp: Add timeout to Store Data requests

Due to a bug in some firmware versions, Store Data requests might not
get an event response in certain situations. As a result, the boot
process will be blocked indefinitely.

Fix this by introducing timeout handling for Store Data requests. In
case a timeout occurs, the Store Data operation is halted and no data
is retrieved from the SCLP facility.

Note: A minority of installed systems rely on Store Data result for
device auto-configuration. These systems will fail to boot in case of a
Store Data timeout and will need to be switched to manual device
configuration as workaround.

Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>