Heads up: New if_xl committed

[Mike Silbersack]

As promised, the updated if_xl with full busdma support / other
improvements has been MFC'd to 4.8-stable.  While I have put this driver
through extensive testing, it is possible that there may be bugs which are
either present in the -current version or that I added in the MFC process.

So, if you cvsup to -stable anytime in the future and notice problems with
if_xl, please tell me ASAP!

Thanks,

Mike "Silby" Silbersack