Update git submodules

* Update docs/submodules/stor4nfv from branch 'stable/fraser'
  - Remove check_envs call

    It was removed because it was useless [1].
    [1] https://build.opnfv.org/ci/view/functest/job/functest-compass-virtual-daily-fraser/772/console

    Change-Id: I7620e959f756bb77e65dd1f770ecdb40e7042629
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
    (cherry picked from commit 6b637d11c99450ed0a1f3b9a5231ccea82e5cd5b)

diff --git a/docs/submodules/stor4nfv b/docs/submodules/stor4nfv
index 3f654aa..4e9176d 160000 (submodule)
--- a/docs/submodules/stor4nfv
+++ b/docs/submodules/stor4nfv
@@ -1 +1 @@
-Subproject commit 3f654aa9b1e19eb9d84b0632a5bc1e7bde96c281
+Subproject commit 4e9176dad81964318224be71d25fd8ee75dac179