Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 2b931c4576d45848ea8d231dd5a4dd1fffd9ba88
  - Merge "Update security scan mail publisher for releng utils and xci"
  - Update security scan mail publisher for releng utils and xci

    Change-Id: Id235b477c3c69aef214943c6a3eb2dd559814e7d
    Signed-off-by: Fatih Degirmenci <fdegir@gmail.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index a4c2cca..2b931c4 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit a4c2cca3a5a0bc6deecbb87f42259d3199bbf30a
+Subproject commit 2b931c4576d45848ea8d231dd5a4dd1fffd9ba88