main/postmarketos-ui-glacier: enable the mce and usb-moded services

mce is used for power management mainly

usb-moded is used for various USB configurations and related settings

This resolves warnings in the tinydm log where it reports nothing provides the DBus service "com.nokia.mce". The Qemu changes are to stop mce from locking the screen on Qemu where that is obviously undesired behaviour.