virtio: Put the virtio under the virtualization menu

This patch moves virtio under the virtualization menu and changes virtio
devices to not claim to only be for lguest.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index c83e1c9..41962e7 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -53,5 +53,6 @@
 # OK, it's a little counter-intuitive to do this, but it puts it neatly under
 # the virtualization menu.
 source drivers/lguest/Kconfig
+source drivers/virtio/Kconfig
 
 endif # VIRTUALIZATION