s390/numa: use correct type for node_to_cpumask_map

With CONFIG_CPUMASK_OFFSTACK=y cpumask_var_t is a pointer to a CPU mask.
Replace the incorrect type for node_to_cpumask_map with cpumask_t.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
4 files changed