drm/i915: Make intel_detect_preproduction_hw easier to extend

drm/i915: Make intel_detect_preproduction_hw easier to extend

As we add new generations, we should keep detecting new pre-production
system development platforms that were temporarily enabled to facilitate
initial development and now superseded by production systems. To make
it easier to add more platforms, split the if into a series of logical
operations.

v2: s/sdv/pre/ - not all system development vehicles are for
preproduction usage.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: "Zanoni, Paulo R" <paulo.r.zanoni@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170130104458.2653-1-chris@chris-wilson.co.uk
Acked-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>