drm/i915: split clock gating init into per-chipset functions

This helps contain the mess to init_display() instead.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
3 files changed