dt-bindings: interconnect: OSM L3: Add SM6375 CPUCP compatible

SM6375 includes a CPUCP block responsible for managing different APSS-
related tasks, such as scaling the voltage and frequency of the
components within the ARM DSU cluster. Add a compatible for the L3 cache
DVFS scaler within.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20230303-topic-sm6375_features0_dts-v2-2-708b8191f7eb@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>