KVM: ia64: Enable virtio driver for ia64 in Kconfig

kvm/ia64 uses the virtio drivers to optimize its I/O subsytem.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/arch/ia64/kvm/Kconfig b/arch/ia64/kvm/Kconfig
index 7914e48..8e99fed 100644
--- a/arch/ia64/kvm/Kconfig
+++ b/arch/ia64/kvm/Kconfig
@@ -46,4 +46,6 @@
 config KVM_TRACE
        bool
 
+source drivers/virtio/Kconfig
+
 endif # VIRTUALIZATION