ARM: dts: qcom: msm8974: Add compat qcom,msm8974-dsi-ctrl to dsi1

Extend the secon DSI interface with the SoC-specific compat entry,
following the change for the first DSI interface.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230110055433.734188-1-dmitry.baryshkov@linaro.org