clk: qcom: kpss-xcc: convert to parent data API

Convert the driver to parent data API. From the Documentation pll8_vote
and pxo should be declared in the DTS so fw_name can be used instead of
parent_names. .name is changed to the legacy pxo_board following how
it's declared in other drivers.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Link: https://lore.kernel.org/r/20220914144743.17369-2-ansuelsmth@gmail.com


Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>