Boot services tend to fail in the middle when the kernel loads a sepolicy live.
It seems that moving full patch (allow magisk * * *) to late_start is still not enough to fix service startup failures.
So screw it, apply all patched in magiskinit, which makes sure that all rules are only loaded in a single step.
The only down side is that some OEM with a HUGE set of secontexts (e.g. Samsung) might suffer a slightly longer boot time, which IS the reason why the rules are split to 2 parts in the first place.
1. Introduce new applet: imgtool for better separation from the main program
2. Actually mount the image and check statvfs for free space in the image
This shall eliminate any possible module installation failure from image resizing issues.
It's not important to check the return value of unlink(2) or even verify
that the file exists. If this code is running, it means the system has
rebooted, and thus the update file, if any, should be removed so that
MagiskManager doesn't keep displaying the same message. We also handle
this before we handle "disable" so that disabled modules don't keep
requesting a reboot to update.