[PATCH 6/6] binman: Move stage header into a CBFS attribute

[Simon Glass]

cbfsutil completely changed the way that stages are formatted in CBFS.
Adjust the binman implementation to do the same.

This mirrors commit 81dc20e744 in coreboot.

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

 tools/binman/cbfs_util.py      | 64 +++++++++++++++++++++-------------
 tools/binman/cbfs_util_test.py |  7 ++--
 2 files changed, 42 insertions(+), 29 deletions(-)

Applied to u-boot-dm, thanks!