arm64: dts: allwinner: h616: enable DVFS for all boards

arm64: dts: allwinner: h616: enable DVFS for all boards

With the DT bindings now describing the format of the CPU OPP tables, we
can include the OPP table in each board's .dts file, and specify the CPU
power supply.
This allows to enable DVFS, and get up to 50% of performance benefit in
the highest OPP, or up to 60% power savings in the lowest OPP, compared
to the fixed 1GHz @ 1.0V OPP we are running in by default at the moment.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>