Warn about Syslinux's reboot.c32 and poweroff.c32 requiring APM
APM is old and some motherboard firmwares have removed support for it.
reboot.c32
and poweroff.c32
will not work on such firmwares. See https://wiki.archlinux.org/index.php/Syslinux#Reboot_and_power_off .
Add a help text to "Reboot
" and "Power Off
" boot menu entries that warns about requiring APM.