Set it based on hint.acpi.0.rsdp. Initially, hint.acpi.0.disabled will be
respected. "Using System Defaults" will override whether it's explicitly
disabled by hint and re-load it based on whether it's present on the system.
Unlike the 4th version, this is not restricted to x86. I have no strong
reasoning for this, so this is definitely open to change.
This submenu is likely going to go away in favor of kernel selection as it
is done in forth at the moment, but for the time being don't descend into it
if we have no kernels available for listing.
These are the .lua files from from Pedro Souza's 2014 Summer of Code
project. Rui Paulo, Pedro Arthur and Wojciech A. Koszek also
contributed.
Obtained from: https://wiki.freebsd.org/SummerOfCode2014/LuaLoader
Sponsored by: Google Summer of Code
Improve the SoC lua menu code to bring it in line with forth
menu functionality
Submitted by: Zakary Nafziger
Sponsored by: FreeBSD Foundation
Use loader.setenv and loader.unsetenv instead of loader.perform
Convert from include("/boot/foo.lua") to foo = require("foo");
to bring in line with latest lua module conventions.
Enforce a uniform style for the new .lua files:
o hard tab indenation for 8 spaces
o don't have if foo then bar; else bas; end on one line
MFC After: 1 month
Relnotes: yes
Differential Review: https://reviews.freebsd.org/D14295
