[S390] topology,sched: fix cpu_coregroup_mask/cpu_book_mask definitions

Both functions take an int instead of an unsigned int. Fixes these
compile warnings:

kernel/sched.c:7167:2: warning: initialization from incompatible pointer type
kernel/sched.c:7170:2: warning: initialization from incompatible pointer type

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>