dt-bindings: clock: qcom, dispcc-sm6125: Require GCC PLL0 DIV clock

The "gcc_disp_gpll0_div_clk_src" clock is consumed by the driver, will
be passed from DT, and should be required by the bindings.

Fixes: 8397c9c0 ("dt-bindings: clock: add QCOM SM6125 display clock bindings")
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Patchwork: https://patchwork.freedesktop.org/patch/548966/
Link: https://lore.kernel.org/r/20230723-sm6125-dpu-v4-5-a3f287dd6c07@somainline.org


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>