drm/i915: Use paramtrized WRPLL_CTL()

v2: Rebase due to SKL_DPLLx usage

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1442595836-23981-21-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
3 files changed