KVM: cleanup "*new.rmap" type

The type of '*new.rmap' is not 'struct page *', fix it

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 4a71faa..78ed71a 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -600,7 +600,7 @@
 	/* Allocate if a slot is being created */
 #ifndef CONFIG_S390
 	if (npages && !new.rmap) {
-		new.rmap = vmalloc(npages * sizeof(struct page *));
+		new.rmap = vmalloc(npages * sizeof(*new.rmap));
 
 		if (!new.rmap)
 			goto out_free;