drm/i915/cfl: Add Coffee Lake PCI IDs for U Sku.

Add PCI Ids for U Skus of Coffeelake.

v2: Use intel_coffeelake_gt3_info, in accordance to-
Rodrigo's patch:

v3: rebased

v3: Remove unused INTEL_CFL_IDS(Rodrigo).

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1496965267-21725-3-git-send-email-anusha.srivatsa@intel.com