dt-bindings: clock: Add Qualcomm SC8280XP display clock bindings

The Qualcomm SC8280XP platform has two display clock controllers, add a
binding for these.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220926203800.16771-2-quic_bjorande@quicinc.com