vppinfra: add vec128_t, vec256_t and vec512_t types
vppinfra: add vec128_t, vec256_t and vec512_t types

Convenient for type conversion

Type: improvement
Change-Id: I35a770e06e6318fb4249b70021ed6f6c93b07162
Signed-off-by: Damjan Marion <9141bba8b2efed526e55cf796d48631af330ad98@cisco.com>

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