While we do plan to switch to OF_SEPARATE now it is supported, it seems
worth at least showing how OF_EMBED could be used instead, just for the
record.
So make the Makefile rule conditional on OF_SEPARATE and adjust fdtdec
to avoid a build error when OF_EMBED is used.
Finally. the dtb symbol has a double underscore, so update it to avoid a
build warning.
With future patches, OF_EMBED will no-longer be used with the EFI app,
so it is expected that it will eventually stop working.
Signed-off-by: Simon Glass <sjg@chromium.org>
Fixes: 2e7bf25f6b ("Support separate DTB files with the UEFI app")
e6eed34cc7