Update git submodules

* Update docs/submodules/doctor from branch 'master'
  - option: "update_neutron_port_dp_status"

    This patch introduces new boolean option "update_neutron_port_dp_status",
    which disabled by default.

    Change-Id: Iaf7503d5854251fabf816b9bf3fcc1964c231a68
    Signed-off-by: Ryota MIBU <r-mibu@cq.jp.nec.com>

diff --git a/docs/submodules/doctor b/docs/submodules/doctor
index 1336b9a..9f91aba 160000 (submodule)
--- a/docs/submodules/doctor
+++ b/docs/submodules/doctor
@@ -1 +1 @@
-Subproject commit 1336b9add0dc6fb91fbf71431e3bfa1cd0dd89d6
+Subproject commit 9f91aba7ef33d7ad88c3bd004fdf7c5fef65f151