The existing distro scripts check extlinux and scripts before EFI. Adjust
the default ordering to do the same, to avoid breaking existing flows.

Add some documentation, mentioning that this order will likely change in
future.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reported-by: Da Xue <da@libre.computer>

This name is a little confusing since it suggests that it sets up the
sibling block device. In fact it sets up a bootdev for it. Rename the
function to make this clearer.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>

We use the terms 'distro' to mean extlinux but they are not really the
same. 'Distro' could refer to any method of booting a distribution,
whereas extlinux is a particular method.

Also we sometimes use syslinux, but it is better to use the same term in
all cases.

Rename distro to syslinux and also update bootstd uses of syslinux to use
extlinux instead.

Signed-off-by: Simon Glass <sjg@chromium.org>

These flags actually relate to the iterator, not the bootflow struct
itself. Rename them.

Signed-off-by: Simon Glass <sjg@chromium.org>

We need to support a basic set of filesystems for booting to work in most
cases. Add these in via a new option, letting the board disable them
individually (for space reasons) if desired.

This enables the filesystem commands as well as the actual functionality,
even though bootstd is quite happy to use ext4 without the ext4 command.
Further work would be needed to disintangle this and reduce code size.

Add several other options as well, providing sensible defaults.

We cannot enable this by default, since it expands the size of many
boards quite a lot.

Signed-off-by: Simon Glass <sjg@chromium.org>

Document the hunters and the new way that iteration works.

Signed-off-by: Simon Glass <sjg@chromium.org>

We need extensions to be set up before we start trying to boot any of the
bootdevs. Add a new priority before all the others for tht sort of thing.
Also add a 'none' option, so that the first one is not 0.

While we are here, comment enum bootdev_prio_t fully and expand the test
for the 'bootdev hunt' command.

Signed-off-by: Simon Glass <sjg@chromium.org>

Replace 'disto' with 'distro' since they are all functions about distro
booting.

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>

These typos were found while reading the docs.

Signed-off-by: Paul Barker <paul.barker@sancloud.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

Add some documentation updates, particularly about global bootmeths.

Signed-off-by: Simon Glass <sjg@chromium.org>