Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Update comments around various structs.

Add speeds S800, S1600 and S3200

Start each of the license/copyright comments with /*-, minor shuffle of lines

Change u_intXX_t to uintXX_t. Change a couple of 'unsigned long's to
uint32_t where appropriate.

Phy register map.