Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - xci: Reduce noise during bootstrapping

    There is too much noise when XCI is cloning repositories, installing
    packages etc so lets make the console output somewhat more readable.

    Change-Id: I15667e0349f943ad5488daf0e3cea9336c9166d1
    Signed-off-by: Markos Chandras <mchandras@suse.de>

diff --git a/docs/submodules/releng-xci b/docs/submodules/releng-xci
index 304a45b..55916bc 160000 (submodule)
--- a/docs/submodules/releng-xci
+++ b/docs/submodules/releng-xci
@@ -1 +1 @@
-Subproject commit 304a45bbdc52aa5e7f4374d027e4e17f42d2cd75
+Subproject commit 55916bc06fe49653441c899f9982e16ef1ef894b