XIP: adopt perfect hash to map struct xip_route_proc

Mapping XID types to struct xip_route_proc is an important step in
forwading, and given that the previous code was using a simple
hash table, XIP forwarding could behave slower if XID types were
placed in the same bucket.
XIP: adopt perfect hash to map struct xip_ppal_ctx
XIP: adopt perfect hash to map struct xia_socket_proc