Update git submodules

* Update docs/submodules/fuel from branch 'master'
  - [mcp] Bring in dpdk scenario support

    Change-Id: Ifd6d61026a0e98e8faf59c7d218333122d70ffe9
    Signed-off-by: Michael Polenchuk <mpolenchuk@mirantis.com>

diff --git a/docs/submodules/fuel b/docs/submodules/fuel
index ecfbd90..f19e006 160000 (submodule)
--- a/docs/submodules/fuel
+++ b/docs/submodules/fuel
@@ -1 +1 @@
-Subproject commit ecfbd90af36439bcb51ec2cace0d0d2340e9fee1
+Subproject commit f19e006f84e98bdee061d79e68c316364251dcbc