LISP: Add APIs for enable/disable xTR/P-ITR/P-ETR modes
LISP: Add APIs for enable/disable xTR/P-ITR/P-ETR modes

Change-Id: Ieeb3b7eaabb568180320fe54d3eae2d26f3e4704
Signed-off-by: Filip Tehlar <9891019d6f5d48a43af8fb71dfec78974db6001d@cisco.com>

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