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

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

Update the mxge(4) driver's copyright to 2007, and drop
the binary distribution clause.

Approved by: re (bmah)

10GbE mode driver and binary firmware for Myricom's PCI-express NICs.
More info regarding these nics can be found at http://www.myri.com.

Please note that the files
sys/dev/myri10ge/{mcp_gen_header.h,myri10ge_mcp.h} are internally
shared between all our drivers (solaris, macosx, windows, linux, etc).
I'd like to keep these files unchanged, so I can just import newer
versions of them when the firmware API/ABI changes. This means I'm
stuck with some of the crazy-long #define names, and possibly
non-style(9) characteristics of these files.

Many thanks to mlaier for doing firmware(9) just as I
needed it, and to scottl for his helpful review.

Reviewed by: scottl, glebius
Sponsored by: Myricom Inc.