Integration of ModemManager in Oniro platform

Description

To enable cellular data connectivity we use ModemManager in combination with NetworkManager in Oniro. This issues ensures that the basic integration in Yocto is all we need or if we need to adjust to our needs.

Ensure ModemManager recipes in Oniro are working and tools like mmcli are functional
Decide if ModemManager should go into every build or only if enabled as MACHINE feature
Verify ModemManager gets picked up by NetworkManager when installed in the image
Upstream fixes, if any

Edited Jul 22, 2022 by Stefan Schmidt

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