HACK: ARM64: dts: rockchip: Hack out PWM regulators on gru

HACK: ARM64: dts: rockchip: Hack out PWM regulators on gru

Until we get PWM regulator solid, let's hack it out and just keep
whatever the firmware set for us.

Note that when the kernel boots it appears that it does some reparenting
of clocks and the PWM frequency actually changes.  ...but the voltage
seems OK ish.

Change-Id: I3be6ea4460f685e4a75a0f7f31f767f09b908442
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-on: https://chrome-internal-review.googlesource.com/254650
Reviewed-by: Stephen Barber <smbarber@google.com>
Tested-by: Doug Anderson <dianders@google.com>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
(Fixes the typo)