Commit 7b159b55d6398d2d240817276ae27ed68f11deda breaks ABI?

[Matthew Garrett]

The change to make GetBrightness calls return unsigned values breaks
g-p-m on 0.5.9, since it now assumes that values are unsigned and breaks 
with the signed ones. Could this be reverted rather than breaking 
visible ABI? Right now g-p-m effectively breaks on any released version 
of hal, which is less than ideal.

-- 
Matthew Garrett | mjg59 at srcf.ucam.org