thermal/drivers/thermal_of: Add change_mode ops support for thermal_of sensor

The sensor driver which register through thermal_of interface doesn't
have an option to get thermal zone mode change notification from
thermal core.

Add support for change_mode ops in thermal_of interface so that sensor
driver can use this ops for mode change notification.

Signed-off-by: Manaf Meethalavalappu Pallikunhi <quic_manafm@quicinc.com>
Link: https://lore.kernel.org/r/1646767586-31908-1-git-send-email-quic_manafm@quicinc.com


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