Update git submodules

* Update docs/submodules/apex from branch 'master'
  - Merge "Removing the downloaded libvirt-client for the iso build"
  - Removing the downloaded libvirt-client for the iso build

    JIRA: APEX-529

    Change-Id: I09970847833d3e182a7485c051e2e46d394cfeff
    Signed-off-by: Dan Radez <dradez@redhat.com>

diff --git a/docs/submodules/apex b/docs/submodules/apex
index 16fa09b..cbac195 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit 16fa09bb892289f3997ef14ed6cbe5a278ee342a
+Subproject commit cbac19523534a3ffe767c6e44015302222d88a0a