thermal: Explicitly enable non-changing thermal zone devices

Some thermal zone devices never change their state, so they should be
always enabled.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Reviewed-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200629122925.21729-9-andrzej.p@collabora.com