This question comes up every now and then with people coming from Linux.
Add some notes about it so we can point to it in the mailing list.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

This file is about 10 years old and the updates have not covered
everything that has changed, particularly in the last few years. Update
the information and add mention of the u-boot.dtsi files.

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

Fix typos.
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

Move this to rST format, largely unchanged to start with. Add an index
for this topic, as well as an empty intro.

Note this patch does not include updates! Is it just a conversion to the
new format. See the next patch.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Heinrich Schuchart <xypron.glpk@gmx.de>