KBI bump in r227697?

[Matthew Jacob]

> This is r229703 for stable/9.
> The __FreeBSD_version was already bumped after that change, at least 3 times.
> In fact, the bump to 900501 in r229723 is almost immediately after it.
>
> For HEAD, it makes no sense to bump the revision at all, since you are
> assumed to always run latest HEAD.
Really? This puzzles me. You're not really supposed to make KBI changes 
in stable- otherwise stable isn't a stable place for vendor KOBJs.

When you make KBI changes, independent of whether head or not, a 
revision bump is useful so that dependent code knows when it has to 
change. This change carries forward and backwards for compilation 
independent of which branch this is in.