Update git submodules

* Update docs/submodules/dovetail from branch 'master'
  - Bugfix: Move userconfig directory into dovetail/dovetail

    JITA: DOVETAIL-449

    1. Dovetail cvp.0.1.0 link dovetail/dovetail to
       /usr/local/lib/python2.7/dist-packages/dovetail/
    2. The directory dovetail/userconfig is lost in this image
    3. Move dovetail/userconfig into dovetail/dovetail/userconfig

    Change-Id: I9da8389e02d92f35879ff5c6a1db1b7d984dd862
    Signed-off-by: xudan <xudan16@huawei.com>

diff --git a/docs/submodules/dovetail b/docs/submodules/dovetail
index 9de3050..21563d9 160000 (submodule)
--- a/docs/submodules/dovetail
+++ b/docs/submodules/dovetail
@@ -1 +1 @@
-Subproject commit 9de3050873909448d675a47326cd4f153a47bef2
+Subproject commit 21563d9f2ed1da2161e23769da090ba8320c6d7f