dt-bindings: sdhci-omap: Add note for cpu_thermal

The driver fetches a thermal zone using the string "cpu_thermal" for
tuning operation. Add a note for the same.

Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
1 file changed