* Enable additional hardware drivers in Linux for better bare metal
display, network & input device compatibility
* Disable ATA-over-Ethernet support, because it spams the network
with unnecessary packets, is basically useless for bootstrapping,
and may even be a security risk
* Increase Fiwix initrd size to 1280MB to fit a larger Linux build
* Make the Fiwix kexec size configurable the same way as initrd
(and reduce from 280MB to 256MB which is sufficient in my testing)
* Use a more conservative memory map for Fiwix & Linux
* Boot Linux with consoleblank=0 on bare metal, so the build won't
go blind after 5 minutes
* Support kexec-fiwix with interrupts disabled (will be useful later
when builder-hex0 is updated)
* Use -S32 -H64 --force to trick sfdisk into allowing MiB-aligned
partitions on a drive that reports a CHS geometry
* Explicitly create partition at sector 2097152 (=1GiB)
* Force mkfs.ext4 to overwrite any existing filesystem it might find
* Wait up to 2 minutes for the disk to become readable (especially
USB drives often show up with a delay)
With this, finalize_fhs.sh can be rerun as needed, e.g. when rebooting.
Also, the preferred nameserver will persist after DHCP.
Thanks to devtmpfs, we no longer need to manage /dev once Linux is up.
There is nothing temporary about our "tmpdir" - its sole purpose is to
contain the final product of the bootstrap process. Thus, removing it
at the end of bootstrap amounts to doing the entire process for nothing.
To remedy this, --tmpdir is renamed --target, keeping the -t short form,
and defaulting to "target" instead of "tmp" to make its purpose clearer.
The --preserve option is removed, as the target is now always preserved.
These are implemented as dummy jumps with a script that just exits
with success. Since this script will be sourced, rather than called,
this causes the bootstrap process to exit at that point.
The breakpoints are conditional on INTERNAL_CI (we check for "pass1"
because that's the only pass when script-generator runs, but the
resulting effect is that each pass only bootstraps its own part of
the manifest).
Linux's KBUILD doesn't follow SOURCE_DATE_EPOCH, but rather it
uses its own variable, KBUILD_BUILD_TIMESTAMP.
While we are at it, also update kexec-linux's checksum, which
didn't match either. (This one was reproducible, it was just
out of date.)
