Update git submodules

* Update docs/submodules/compass4nfv from branch 'master'
  - Merge "Set NEUTRON_MECHANISM_DRIVERS according to ODL plugin"
  - Set NEUTRON_MECHANISM_DRIVERS according to ODL plugin

    JIRA: COMPASS-604

    when ODL plugin is enable, set NEUTRON_MECHANISM_DRIVERS
    to opendaylight, otherwise set to openvswitch

    Change-Id: I25140990b154bdc772773fdbee95526837431a6e
    Signed-off-by: Harry Huang <huangxiangyu5@huawei.com>

diff --git a/docs/submodules/compass4nfv b/docs/submodules/compass4nfv
index f507b0e..2f55e49 160000 (submodule)
--- a/docs/submodules/compass4nfv
+++ b/docs/submodules/compass4nfv
@@ -1 +1 @@
-Subproject commit f507b0e1399bf86adc0ebe7272c89313b7ad3a43
+Subproject commit 2f55e496b03038296b59d4fb2c0dbf1af3223226