vppinfra: AVX2 interleave functions
vppinfra: AVX2 interleave functions

Change-Id: I8688f700fccd87484da3e202ca3a070cc14eb267
Signed-off-by: Damjan Marion <9141bba8b2efed526e55cf796d48631af330ad98@cisco.com>

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