drm: ci: igt_runner: Remove todo

/sys/kernel/debug/dri/*/state exist for every atomic KMS driver.
We do not test non-atomic drivers, so remove the todo.

Acked-by: Helen Koike <helen.koike@collabora.com>
Signed-off-by: Vignesh Raman <vignesh.raman@collabora.com>
Signed-off-by: Helen Koike <helen.koike@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231207091831.660054-2-vignesh.raman@collabora.com