main/postmarketos-ui-plasma-mobile: clean up runtime deps
- plasma-nm-mobile is already a dep of plasma-phone-components
- ofono is already a dep of plasma-phone-components
- ofono-openrc already gets pulled in automatically through openrc and ofono
- networkmanager is already pulled in by plasma-nm-mobile
- qt5-qtvirtualkeyboard has been replaced by maliit ages ago