vlxlan-gpe - fix api registering
vlxlan-gpe - fix api registering

(was registering span api twice instead)

Change-Id: I196d520061d10872fd795c0b1115574591e8d978
Signed-off-by: Gabriel Ganne <54ed6f2b99047a4f6b8431ec375373608f566aee@qosmos.com>

FDio/vpp,milanlenco/vpp,chrisy/vpp,vpp-dev/vpp,chrisy/vpp,vpp-dev/vpp,milanlenco/vpp,FDio/vpp,vpp-dev/vpp,vpp-dev/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,vpp-dev/vpp,chrisy/vpp,vpp-dev/vpp,FDio/vpp,milanlenco/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,milanlenco/vpp,milanlenco/vpp,FDio/vpp,vpp-dev/vpp,chrisy/vpp,FDio/vpp,milanlenco/vpp