greybus: control: add bundle deactivate and activate operation

Add the AP implementation for the Greybus Control Bundle Deactivate
Operation. This operation requests a Bundle to enter the BUNDLE_OFF
state. All Connections associated with the Bundle must be closed prior
sending this operation.

Add the AP implementation for the Greybus Control Bundle Activate
Operation. This operation requests a specific Bundle to transition from
the BUNDLE_OFF state to the BUNDLE_ACTIVE state.

[elder@linaro.org: fixed a typo pointed out by Johan]

Signed-off-by: David Lin <dtwlin@google.com>
Reviewed-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Alex Elder <elder@linaro.org>