drm/i915: move has_pooled_eu to runtime info

If it's modified runtime, it's runtime info.

Curiously, the flag was never initialized statically.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Maarten Lankhort <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/db6d47abd87c74ae5f5be1cda62af13518c896fb.1660910433.git.jani.nikula@intel.com