hyperv/hn: Apply VF's RSS setting

Since in Azure SYN and SYN|ACK go through the synthetic parts while the
rest of the same TCP flow goes through the VF, apply VF's RSS settings
to synthetic parts to have a consistent hash value/type for the same TCP
flow.

Sponsored by:   Microsoft
Differential Revision:  https://reviews.freebsd.org/D12333

hyperv/hn: Fix options RSS building

Reported by:    np
Sponsored by:   Microsoft