ota: Disable downgrade check

We want users to be able to downgrade their packages.

Change-Id: I6bcbd4ee2a02640fe0855b0f1f197a02e914c927
roomservice: Fix handling of devices with _ in their name

Currently, roomservice takes every _ in the device tree name and
replaces it with /

Instead, strip the device name (such as pollux_windy) from the repo
name before replacing _ with / and then append it again when we're done

Change-Id: Ieabe85ecd8829c959a7296e5cd73f577879c4ffc
Add more info while flashing

Thanks to @mithun46