Update git submodules

* Update docs/submodules/stor4nfv from branch 'stable/fraser'
  - update k8-nosdn-stor4nfv-ha scenario documentation

    Change-Id: Iea38168d2819cbbedcfcc799dfd93840aaf53d4a
    Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>

diff --git a/docs/submodules/stor4nfv b/docs/submodules/stor4nfv
index 91625f4..1892f36 160000 (submodule)
--- a/docs/submodules/stor4nfv
+++ b/docs/submodules/stor4nfv
@@ -1 +1 @@
-Subproject commit 91625f4898dcdcba64f1941c6c56f13938c9d4ea
+Subproject commit 1892f3672a2bbe8d0a7d8b3cdb5687d9e0208e4d