greybus: db3(arche)-platform: Remove all APB control code

Current db3(arche)-platform driver was only handling APB control signals,
which is where it all started. But now with completion of DB3/EVT1 bringup
we know that platform driver is more than APB control.

We have to bring SVC up before APB, as SVC supposed to enable
clock to APB's. Note that, in EVT1, AP will have direct control over
APB's clock.
Then we have dependency between APB and USB HUB, where, APB should be
brought up before USB HUB (note that this needs to rootcaused).

This patch cleanup the db3(arche)-platform driver to remove all APB control
code. The idea here is create another driver for APB control
(arche-apb-ctrl.c), which will deal with APB.
And this driver will have generic/common platform specific support,
currently manages SVC resources.

This patch also takes in all the changes from factory branch, discovered
during bringup.
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>