[pkg-upd] 2021.07-4

• Clear separation of the PinePhone-specific utilities ("/usr/bin/pp-"; hint: "pp") and associated configuration files ("/etc/pinephone/.conf")
• The above-described layout will also be used in the future PinePhone thermal daemon, ensuring a coherent layout and resulting in fewer inotify events for the thermal daemon
• Various U-Boot utilities now perform a lot of error checking and validation, and malicious commands can no longer be injected into the U-Boot configuration file
• Mount options for the /boot partition are now improved to prevent existence of executable and device files, and not to show all files as executable
• The systemd service for the preparation of mount points is now self-disabled in the service file, and it is no longer enabled on U-Boot package updates
• The utility for creating the U-Boot boot script no longer needs to be placed in the /boot directory and executed from that directory
• Various code cleanups and inclusion of comments that document things such as the GPIO lines used in the U-Boot boot script