Update git submodules

* Update docs/submodules/doctor from branch 'master'
  - change test_case option

    This patch changes the way to specify target test case to be run,
    'test_fault_management' --> 'fault_management'.

    Also, the default is set to 'fault_management'. The reason to this
    is not to block any other on-going activities for Fraser release.

    Change-Id: I92305477a84ffa0e703c36d309fbdf97435782aa
    Signed-off-by: Ryota MIBU <r-mibu@cq.jp.nec.com>

diff --git a/docs/submodules/doctor b/docs/submodules/doctor
index 8b4fa81..ffb5048 160000 (submodule)
--- a/docs/submodules/doctor
+++ b/docs/submodules/doctor
@@ -1 +1 @@
-Subproject commit 8b4fa81e06057e2e0fbda2071c6fbf46cda7a45f
+Subproject commit ffb504843611959b983614bd7b316cd3c205fd49