please test i915 (nvidia alignment fix)

[coypu%SDF.ORG@localhost]

Hi!

I've committed something that is supposed to help
with the console appearing broken on most nvidia
hardware here:
http://mail-index.netbsd.org/source-changes/2016/12/12/msg079782.html

The code is shared with i915 (but not radeon, at
least not yet). I'd really love if someone
confirmed that i915 is not horribly broken, so
it could be pulled up to netbsd-7 (I have no
Intel graphics hardware).

radeon should be unaffected.

Thanks.