drm/msm/dp: stop parsing clock names from DT

All supported platforms use the same clocks configuration. Instead of
parsing names from DT in a pretty complex manner, use the static
configuration. If at some point newer (or older) platforms have
different clock configuration, this clock config can be moved to the
device data.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Tested-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Patchwork: https://patchwork.freedesktop.org/patch/576115/
Link: https://lore.kernel.org/r/20240126-dp-power-parser-cleanup-v3-7-098d5f581dd3@linaro.org