[PATCH v3] binman: Get futility by building it

[Simon Glass]

A binary download is not great, since it depends on libraries being
present in the system. Build futility from source instead.

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

Changes in v3:
- Drop the branch, just use master instead
- Explain why we are using a mirror
- Drop mention of upstream patches as they are applied

Changes in v2:
- Pull from github instead, to avoid needing to login / gitcookies

 tools/binman/bintool.py        | 10 +++++++---
 tools/binman/btool/futility.py | 17 +++++++++++++----
 2 files changed, 20 insertions(+), 7 deletions(-)

Applied to u-boot-dm, thanks!