lockscreen: show device name
It is useful to see the name of the device before you unlock it. For example, if you have multiple BitBoxes, it is useful to know which one is inserted before entering long passwords or passphrases.
The device name is not a secret, and can already be queried in the API at any time, also before unlock.
Users that dislike this can change the device name in the settings to something generic.
Truncation here does not work well because the font is not monospace. I tried a monospace font - it wastes a lot of space and looks a bit ugly. It would be best to either autoscroll the name if it is too long, or to truncate based on actual size, not based on the number of chars. I'll try that later.
I changed the code to take the actual rendered size of the name into account.