pc: Initializing ram_memory under Xen.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
CC: qemu-stable@nongnu.org
diff --git a/xen-stub.c b/xen-stub.c
index 47c8e73..ad189a6 100644
--- a/xen-stub.c
+++ b/xen-stub.c
@@ -64,7 +64,7 @@
 {
 }
 
-int xen_hvm_init(void)
+int xen_hvm_init(MemoryRegion **ram_memory)
 {
     return 0;
 }