KVM: s390: Cleanup kvm_arch_init error path

Both kvm_s390_gib_destroy and debug_unregister test if the needed
pointers are not NULL and hence can be called unconditionally.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/kvm/20191002075627.3582-1-frankja@linux.ibm.com


Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>