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>

drivers/Kconfig

@@ -91,6 +91,4 @@ source "drivers/dca/Kconfig"
 source "drivers/auxdisplay/Kconfig"
 
 source "drivers/uio/Kconfig"
-
-source "drivers/virtio/Kconfig"
 endmenu