clk: qcom: mmcc-msm8974: use parent_hws/_data instead of parent_names

Convert the clock driver to specify parent data rather than parent
names, to actually bind using 'clock-names' specified in the DTS rather
than global clock names. Use parent_hws where possible to refer parent
clocks directly, skipping the lookup.

Note, the system names for xo clocks were changed from "xo" to
"xo_board" to follow the example of other platforms. This switches the
clocks to use DT-provided "xo_board" clock instead of manually
registered "xo" clock and allows us to drop qcom_cc_register_board_clk()
call from the driver at some point.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221204124508.1415713-9-dmitry.baryshkov@linaro.org