Update git submodules

* Update docs/submodules/releng from branch 'master'
  - CPERF: fix flavor syntax for csit

    Change-Id: Id3430db201ba82b398c3e74f5c3cbb541c6fb208
    Signed-off-by: Tim Rozet <trozet@redhat.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 36d1c46..3a641fc 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 36d1c46df552a340c3f139d7a0f831d9bb85b5d4
+Subproject commit 3a641fcd1e3e844f134245d212886a062c79ff77