dt-bindings: mfd: qcom,tcsr: Add compatible for MSM8226

Document the qcom,msm8226-tcsr compatible.

Signed-off-by: Matti Lehtimäki <matti.lehtimaki@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230112202612.791455-5-matti.lehtimaki@gmail.com