KVM: x86: mmu: returning void in a void function is strange

Let's just drop the return.
Reviewed-by: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

arch/x86/kvm/mmu.c

@@ -2424,7 +2424,7 @@ static void __shadow_walk_next(struct kvm_shadow_walk_iterator *iterator,
 
 static void shadow_walk_next(struct kvm_shadow_walk_iterator *iterator)
 {
-	return __shadow_walk_next(iterator, *iterator->sptep);
+	__shadow_walk_next(iterator, *iterator->sptep);
 }
 
 static void link_shadow_page(struct kvm_vcpu *vcpu, u64 *sptep,