Otherwise reading information like `qbootctl -a` triggers removal and
readdition of all partitions like:
```
KERNEL[73264.679695] remove /devices/platform/soc@0/1d84000.ufshc/host0/target0:0:0/0:0:0:4/block/sde/sde11 (block)
KERNEL[73264.748249] add /devices/platform/soc@0/1d84000.ufshc/host0/target0:0:0/0:0:0:4/block/sde/sde11 (block)
KERNEL[73264.863286] remove /devices/platform/soc@0/1d84000.ufshc/host0/target0:0:0/0:0:0:4/block/sde/sde11 (block)
KERNEL[73264.917664] add /devices/platform/soc@0/1d84000.ufshc/host0/target0:0:0/0:0:0:4/block/sde/sde11 (block)
UDEV [73264.980859] remove /devices/platform/soc@0/1d84000.ufshc/host0/target0:0:0/0:0:0:4/block/sde/sde11 (block)
UDEV [73265.150742] add /devices/platform/soc@0/1d84000.ufshc/host0/target0:0:0/0:0:0:4/block/sde/sde11 (block)
UDEV [73265.276134] remove /devices/platform/soc@0/1d84000.ufshc/host0/target0:0:0/0:0:0:4/block/sde/sde11 (block)
UDEV [73265.492442] add /devices/platform/soc@0/1d84000.ufshc/host0/target0:0:0/0:0:0:4/block/sde/sde11 (block)
…[the same for all other partitions on sde]…
```
leading to wasted CPU cycles (and battery) but also making programms
that run right after that command and accessing one of the partitions
fail sporadically. This can be bad if those commands are e.g. doing a
```
cat /dev/disk/by-partlabel/boot_a
```
to backup the current boot partition.
For some usecases it is desired to still update the GPT headers even if
the UFS BSG device is missing. Add a new flag which implements this
behaviour.
It isn't made the default because on some platforms this could result in
an unbootable device, there it's preferable to defer to the user by just
bailing out if the UFS BSG device is unavailable.
Signed-off-by: Caleb Connolly <caleb@connolly.tech>
The only C++ was for handling discovering and iterating over the
partitions PER block device, this was implemented in a really
overcomplicated way.
Simplify things, port everything over to c11 and drop the libstdc++
requirement entirely.
