Update git submodules

* Update docs/submodules/qtip from branch 'master'
  - Merge "Optimize Dockerfile"
  - Optimize Dockerfile

    - Add new packages what storperf scripts need : curl and wget
    - Minimize the number of layers
    - ansible is already in requirements.txt, delete the apt-get commands

    Change-Id: Ie04d6618737146674396a7c005a247829f06c1d9
    Signed-off-by: zhihui wu <wu.zhihui1@zte.com.cn>

diff --git a/docs/submodules/qtip b/docs/submodules/qtip
index 7cce634..72f2521 160000 (submodule)
--- a/docs/submodules/qtip
+++ b/docs/submodules/qtip
@@ -1 +1 @@
-Subproject commit 7cce634eea37d7ea25d5c3ae757514333986a8bb
+Subproject commit 72f2521a18aeed7aa3485f98b15eaa325deafa18