thermal: exynos: fix ordering in exynos_tmu_remove()

It might not be a problem currently but unregister/uninitialize things
in the reverse order that they are registered/initialized.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Amit Daniel Kachhap <amit.daniel@samsung.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>