Update git submodules

* Update docs/submodules/releng from branch 'master'
  to 1c7486dfebcf0d0c8b4c7639993443b25c2a47a4
  - Fix pip issues

    Change-Id: Ied4976f69d8e4abd0e2234a0848debf5afdfe2d8
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index efca3e5..1c7486d 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit efca3e578d8beb32ac45fbb691905aa754cf6bae
+Subproject commit 1c7486dfebcf0d0c8b4c7639993443b25c2a47a4