[S390] KVM preparation: split sysinfo definitions for kvm use

drivers/s390/sysinfo.c uses the store system information intruction to query
the system about information of the machine, the LPAR and additional
hypervisors. KVM has to implement the host part for this instruction.

To avoid code duplication, this patch splits the common definitions from
sysinfo.c into a separate header file include/asm-s390/sysinfo.h for KVM use.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>