libglnx: Pick up file permission regression fix

https://bugzilla.gnome.org/747813

diff --git a/libglnx b/libglnx
index 376219a9c276237f21c2c5aa1f0b7875a89586b6..02af92ffefda4251d894f0ec7a3aff9bc26af1cd 160000 (submodule)
--- a/libglnx
+++ b/libglnx
@@ -1 +1 @@
-Subproject commit 376219a9c276237f21c2c5aa1f0b7875a89586b6
+Subproject commit 02af92ffefda4251d894f0ec7a3aff9bc26af1cd