net: Split RNDIS protocol structs/macros out of dev/usb/net/if_urndisreg.h

So that Hyper-V can leverage them instead of rolling its own definition.

Discussed with: hps
Reviewed by:    hps
Sponsored by:   Microsoft
Differential Revision:  https://reviews.freebsd.org/D7592

net/rndis: Add canonical RNDIS major/minor version as of today.

Reviewed by:    hps
Sponsored by:   Microsoft
Differential Revision:  https://reviews.freebsd.org/D7593

net/rndis: Fix RNDIS_STATUS_PENDING definition.

While I'm here, sort the RNDIS status in ascending order.

Sponsored by:   Microsoft
Differential Revision:  https://reviews.freebsd.org/D7594