thermal/drivers/ti-soc-thermal: Remove unused declarations

thermal/drivers/ti-soc-thermal: Remove unused declarations

The functions definition of ti_bandgap_read_thot(),
ti_bandgap_write_thot(), ti_bandgap_read_tcold() and
ti_bandgap_write_tcold() has been removed since commit 9bebf3485c6a
("thermal: ti-soc-thermal: remove dead code"), remain the declarations
untouched in the header files. So, clean up this unused declarations.

Signed-off-by: Zhang Zekun <zhangzekun11@huawei.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20240812125210.94280-1-zhangzekun11@huawei.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>