Remove unused multicast fields from vnet_buffer_t
Remove unused multicast fields from vnet_buffer_t

Change-Id: I8db55443c0beb33a89520ab3167f703f8646ec9e
Signed-off-by: Neale Ranns <b9c0e9ef0223633bc2f318425f615cf5840a0be7@cisco.com>

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