Switch to ModemManager

Meta-task for ModemManager switch

• Port SpaceBar plasma-mobile/spacebar!48 (merged)
• Port Plasma Dialer: plasma-mobile/plasma-dialer!71 (merged)
• New mobile broadband kcm: plasma/plasma-nm!33 (closed) plasma-mobile/plasma-settings!92 (merged)
• SIM unlocking: plasma-nm has a functional PIN dialog. plasma/plasma-nm!66 (merged) makes it a tiny bit more mobile friendly but eventually we want a mobile rewrite of it
• Plasma Shell top indicators (may need to create QML bindings in modemmanager-qt?) https://invent.kde.org/plasma/plasma-phone-components/-/merge_requests/176

sudo pacman -S modemmanager-pp
sudo systemctl stop ofono
sudo systemctl disable ofono
sudo systemctl enable ModemManager
sudo systemctl start ModemManager

@bshah