drm/i915/glk: Plane color correction register changes

In Geminilake, the bits for enabling pipe csc, pipe gamma and plane
gamma moved to a new register. So update the plane update functions
to set the right bits.

Pipe CSC is kept disabled though, since enabling that also enables the
dedicated degamma table, and that is not properly programmed yet,
leading to a black screen.

v2: Use plane_id. (Ville)
    Remove unnecessary variable. (Ville)
    Keep registers in offset order. (Ville)
    Don't set plane gamma disable twice. (Ander)

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Ander Conselvan De Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1485429865-10687-3-git-send-email-ander.conselvan.de.oliveira@intel.com