[Buildroot] [PATCH 08/15 v2] docs/manual: document git backend handling of export-subst attribute

[Yann E. MORIN]

Add the changes about export-subst in the git backend, to the migrating
section of the manual.

Signed-off-by: Yann E. MORIN <yann.morin.1998 at free.fr>
Cc: Arnout Vandecappelle (Essensium/Mind) <arnout at mind.be>
---
 docs/manual/migrating.adoc | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/docs/manual/migrating.adoc b/docs/manual/migrating.adoc
index c0f89cbf07..ed9b61257a 100644
--- a/docs/manual/migrating.adoc
+++ b/docs/manual/migrating.adoc
@@ -123,3 +123,11 @@ LIBFOO_PRE_PATCH_HOOKS += LIBFOO_ARCH_PATCHES
 
 Note that no package in Buildroot has architecture-specific patches, and
 that such patches will most probably not be accepted.
+
+[[migrating-git-attributes]]
+=== Migrating to 2024.05
+
+The git download backend now properly expands the `export-subst`
+https://git-scm.com/docs/gitattributes[git attribute] when generating
+archives; the archive version suffix has been updated, to +-br2+, so the
+hash files must be updated accordingly.
-- 
2.44.0