greybus: arche-platform: merge arche-apb-ctrl and arche-platform

No need to have two separate arche platform drivers, that's just crazy,
so merge them both together to be only one kernel module.

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Reviewed-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Tested-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>