docs: Mention add_intermediate and provide an example

This is a useful feature, so add a note about it.

Change-Id: If29f6480f878bdaf877dc208cc4861b884e10840
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/77342
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Patrick Georgi <patrick@coreboot.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/77465
Tested-by: Patrick Georgi <patrick@coreboot.org>
Reviewed-by: Martin L Roth <gaumless@gmail.com>

0 files changed, 0 insertions, 0 deletions