Merge branch 'bpf-rv64-jit'

Luke Nelson says:

====================
This patch series introduces a set of optimizations to the BPF JIT
on RV64. The optimizations are related to the verifier zero-extension
optimization and BPF_JMP BPF_K.

We tested the optimizations on a QEMU riscv64 virt machine, using
lib/test_bpf and test_verifier, and formally verified their correctness
using Serval.
====================

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>