dt-bindings: timer: Add Nomadik MTU binding

The Nomadik MTU timer has been used in devicetrees forever
but somehow we missed to add a binding for it. Fix it
by simply adding it.

Cc: Lee Jones <lee.jones@linaro.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220526213621.373727-1-linus.walleij@linaro.org


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