librem 5 shipmode broken on Linux 6.3+

Found this patch in upstream librem5-base: https://source.puri.sm/Librem5/librem5-base/-/merge_requests/353

I personally haven't actually experienced this since the 6.3 kernel isn't in the stable branch, but I assume it's broken on edge based on that patch 😄

I added this to the 23.06 milestone, I don't think we want to ship a new stable release with this regression. Without "shipmode", the battery drains quickly when the device is powered off.