Small FBC fix

[damien.lespiau at intel.com (Damien Lespiau)]

I noticed on pre-HSW machines we get a spurious debug message:

[drm:intel_update_fbc], fbc set to per-chip default
[drm:intel_update_fbc], fbc disabled per module param

but the fbc module parameter is not set. This series fixes it up.

-- 
Damien