drm/i915: Fix icl workarounds whitespaces

Align icl workarounds whitespace with the rest of the file

Cc: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20181109145333.10570-2-mika.kuoppala@linux.intel.com