KVM: s390: fix memsize >= 4G

commit 628eb9b8a8f3
    KVM: s390: streamline memslot handling

introduced kvm_s390_vcpu_get_memsize. This broke guests >=4G, since this
function returned an int.

This patch changes the return value to a long.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index ec5eee7..06cce82 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -58,7 +58,7 @@
 int kvm_s390_inject_program_int(struct kvm_vcpu *vcpu, u16 code);
 int kvm_s390_inject_sigp_stop(struct kvm_vcpu *vcpu, int action);
 
-static inline int kvm_s390_vcpu_get_memsize(struct kvm_vcpu *vcpu)
+static inline long kvm_s390_vcpu_get_memsize(struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.sie_block->gmslm
 		- vcpu->arch.sie_block->gmsor