Update git submodules

* Update docs/submodules/ccsdk/distribution.git from branch 'master'
  to 15f406b8210d615f0191108805b0489d3aaa4a38
  - Provide symlink to old ansible root

    For backward compatibility, provide symlink /opt/onap/ccsdk ->
    /opt/ansible-server in ansible server container.

    Change-Id: I935ded656800c6a94b0326dcdd52caaaf0c7a71a
    Issue-ID: CCSDK-1044
    Signed-off-by: Timoney, Dan (dt5972) <dtimoney@att.com>

diff --git a/docs/submodules/ccsdk/distribution.git b/docs/submodules/ccsdk/distribution.git
index 55b6a19..15f406b 160000 (submodule)
--- a/docs/submodules/ccsdk/distribution.git
+++ b/docs/submodules/ccsdk/distribution.git
@@ -1 +1 @@
-Subproject commit 55b6a19742a02fdb854b66efac94fcb86b95378d
+Subproject commit 15f406b8210d615f0191108805b0489d3aaa4a38