serial: msm: Use OPP table for DVFS support

serial: msm: Use OPP table for DVFS support

Parse the OPP table from the device tree and use dev_pm_opp_set_rate()
instead of clk_set_rate() to allow making performance state votes
specified in the OPP table (e.g. for power domains and interconnects).

Without an OPP table in the device tree this will behave just as before
this patch.

Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Link: https://lore.kernel.org/r/20231128-serial-msm-dvfs-v1-2-4f290d20a4be@kernkonzept.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>