libocispec: sync

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>

diff --git a/libocispec b/libocispec
index 69250ffc511a6fd7833744c1dccb67b71e3cb432..bf749566cda632fb2f5dcf9c4eb5bbec71ac7d5f 160000 (submodule)
--- a/libocispec
+++ b/libocispec
@@ -1 +1 @@
-Subproject commit 69250ffc511a6fd7833744c1dccb67b71e3cb432
+Subproject commit bf749566cda632fb2f5dcf9c4eb5bbec71ac7d5f