docs: Redirect top-level make targets to Documentation/

To avoid redundancy about how to call into `Makefile.sphinx`,
only do that from the `Documentation/Makefile` and call into
that from the top level.

Change-Id: I99c462cdaf83d711e4b7c07b713d304274db8cb4
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/77406
Reviewed-by: Paul Menzel <paulepanter@mailbox.org>
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

0 files changed, 0 insertions, 0 deletions