Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge "prototypes: xci: Move host keys away from / directory"
  - prototypes: xci: Move host keys away from / directory

    Putting the host keys in '/' requires root privileges so
    it's best if we place them in the same directory like the
    rest of the XCI files.

    Change-Id: I030ed3d6cbb57bb984a78aeffb4eca2bd5c10bb0
    Signed-off-by: Markos Chandras <mchandras@suse.de>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 331b167..9620b46 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 331b1671696fdc7823332add1f48b6ce90b99c75
+Subproject commit 9620b4676471e8cd21890776f8573112cdd16282