drm/i915 more registers for S3 (DSPCLK_GATE_D, CACHE_MODE_0, MI_ARB_STATE)

Failing to preserve the MI_ARB_STATE register was causing FIFO underruns on
the VGA output on my HP 2510p after resume.

Signed-off-by: Dave Airlie <airlied@redhat.com>
2 files changed