hardware_probe: Fix rogue detection

Some new board, eg. asurada, has the folder but doesn't use rogue.
Instead, we check for the content of the folder to determine rogue.

BUG=b:232574099
TEST=deploy to hana

Change-Id: Ic7c823633a222c8394d63814a456e2962d57c386
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/graphics/+/3805485
Tested-by: Po-Hsien Wang <pwang@chromium.org>
Reviewed-by: Ilja Friedel <ihf@chromium.org>
Commit-Queue: Po-Hsien Wang <pwang@chromium.org>