In 06c92dafb8 (Makefile: allow specifying a SHA-1 for non-cryptographic
uses, 2024-09-26), support for unsafe SHA-1 is added. Add the unsafe
SHA-1 build info to `git version --build-info` and update corresponding
documentation.

Signed-off-by: Justin Tobler <redacted>
---
 Documentation/git-version.adoc | 3 +++
 help.c                         | 8 ++++++++
 2 files changed, 11 insertions(+)

diff --git a/Documentation/git-version.adoc b/Documentation/git-version.adoc
index 80fa7754a6..53c8ba74c1 100644
--- a/Documentation/git-version.adoc
+++ b/Documentation/git-version.adoc

@@ -22,6 +22,9 @@ OPTIONS
 --build-options::
        Include additional information about how git was built for diagnostic
        purposes.
++
+If built to use a faster SHA-1 implementation for non-cryptographic purposes,
+the implmentation used is denoted as "unsafe-SHA-1".