drm/i915: duplicate intel_enable_pll into i9xx and vlv versions
drm/i915: duplicate intel_enable_pll into i9xx and vlv versions

Mostly since I _really_ don't want to touch the vlv hell.

No code change, just duplication. Also kill a now seriously outdated
code comment - the remark about the dvo encoder is now handled with
the pipe A quirk.

v2: Update the BUG_ONs as suggested by Jani (both in vlv_ and i9xx_
functions, since the split happens here).

Cc: Jani Nikula <ba783f3beccaedfda693f41a15407d612a629408@linux.intel.com>
Reviewed-by: Imre Deak <fbd5edba1988036c8923f0cca0cce6ac4811db29@intel.com>
Signed-off-by: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs