Use only a single -machine parameter.
Describe that the same invocation of qemu-system-<arch> has to be
used for dumping the device-tree as will be used when executing U-Boot.
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
QEMU currently generates a devicetree for use with U-Boot. Explain how to
obtain it.
Also explain how to merge it to produce a devicetree with the U-Boot
features included.
Signed-off-by: Simon Glass <sjg@chromium.org>