Update git submodules

* Update docs/submodules/releng-xci from branch 'master'
  - Merge "xci: install-lib: Install curl package"
  - xci: install-lib: Install curl package

    XCI_ANSIBLE_PIP_VERSION is determined dynamically using curl.
    This package is not present on every system, hence fails
    since it can not install a null version of Ansible

    Change-Id: I96a2237e6bdb28e09f0eebee4aae91742973d770
    Signed-off-by: Taseer Ahmed <taseer94@gmail.com>

diff --git a/docs/submodules/releng-xci b/docs/submodules/releng-xci
index a850a90..c84e827 160000 (submodule)
--- a/docs/submodules/releng-xci
+++ b/docs/submodules/releng-xci
@@ -1 +1 @@
-Subproject commit a850a9093da3df7b880e8bfa2a861e72cfc7180f
+Subproject commit c84e827daec8001a9ab1f89beabaa3627cf69eda