overlay: overwrite the qcom init file in the vendor partition

It's still not clear to me how the Ubuntu Touch/Android initialization works: the same init.qcom.rc file needs to be overlayed on the system partition, or the device won't go past the boot logo; and we need to overlay this file on its original path on the vendor partition as well, otherwise the dataqti service does not get disable and continuously restarts (and prevents a successful boot if a SIM card is inserted).

For the time being, let's mask the file on both locations.