dt-bindings: clock: exynos850: Add TMU clock

Add a constant for TMU PCLK clock. It acts simultaneously as an
interface clock (to access TMU registers) and an operating clock which
makes TMU IP-core functional.

Signed-off-by: Sam Protsenko <semen.protsenko@linaro.org>
Link: https://lore.kernel.org/r/20240723163311.28654-1-semen.protsenko@linaro.org


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>