ibcore: Introduce enum ib_raw_packet_caps from Linux 4.11

This enum also exists as enum ibv_raw_packet_caps in libibverbs/verbs.h.

[khng: cherry-picked from Linux
ebaaee253ad3a3c573ab7d3d77e849056bdfa9ea]

Sponsored by: Juniper Networks, Inc.
MFC after: 7 days
Reviewed by: kib, zlei
Differential Revision: https://reviews.freebsd.org/D42177

(cherry picked from commit a69b6af2024fdd501b4bbc674092fb2b6d466364)