vxlan: fix interface naming
vxlan: fix interface naming

Previous commit broke naming of vxlan interfaces.

Type:fix
Fixes:a4b0541f6

Signed-off-by: Ray Kinsella <64a50932049ddff830412e0fd9edb30198bf17f3@ashroe.eu>
Change-Id: I5e304821be73547b4e47c35ad9632283f153830f

chrisy/vpp,FDio/vpp,FDio/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,chrisy/vpp