drm/i915: Specify when the PLL hw state fields are valid
drm/i915: Specify when the PLL hw state fields are valid

Not all those fields are valid on a given platform. Make it explicit.

Unions could also be used, but were cluttering some code paths with
if/else ladders.

v2: Don't use anonymous unions (Daniel)

Signed-off-by: Damien Lespiau <64bd3cb94f359c1a3ce68dae5e26b40578526277@intel.com>
Signed-off-by: Daniel Vetter <c1b6782c4af8f0673da8923a0702a1832e5940f4@ffwll.ch>

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