Update git submodules

* Update docs/submodules/releng from branch 'master'
  - Merge changes I68779792,Ide8d210e

    * changes:
      Export CI_LOOP as expected by Functest
      Export an new var related to Energy in functest jobs

  - Export CI_LOOP as expected by Functest

    Otherwise all testcases are skipped:
    https://build.opnfv.org/ci/view/functest/job/functest-apex-baremetal-daily-master/764/console
    https://build.opnfv.org/ci/view/functest/job/functest-apex-baremetal-daily-master/763/console

    It will be enforced by a similar patch in Functest too.

    Change-Id: I6877979295378ed9ce6b85ad62e8a78e1572b8ba
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
  - Export an new var related to Energy in functest jobs

    It conforms with "Unlink Energy from functest utils and constants":
    https://gerrit.opnfv.org/gerrit/#/c/51943/

    Depends-On: Iecd5d49b4d4c961c9dc51e43e54df1fcd4027266
    Change-Id: Ide8d210eab26451a63911938fe0e1bafcf77c500
    Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>

diff --git a/docs/submodules/releng b/docs/submodules/releng
index 30eb16f..37980c2 160000 (submodule)
--- a/docs/submodules/releng
+++ b/docs/submodules/releng
@@ -1 +1 @@
-Subproject commit 30eb16fb6d7f16bc05258298eeef78732bdd9cf0
+Subproject commit 37980c29656ff34ae0fa8b0bf14ad876382778b3