thermal: core: Remove duplicate struct declaration

The struct thermal_zone_device is already declared on line 32, so the
duplicate declaration has been removed.

Fixes: b1ae92dc ("thermal: core: Make struct thermal_zone_device definition internal")
Signed-off-by: xueqin Luo <luoxueqin@kylinos.cn>
Link: https://lore.kernel.org/r/20250206081436.51785-1-luoxueqin@kylinos.cn


Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>