Update git submodules

* Update docs/submodules/doctor from branch 'master'
  - Gambia release notes

    Change-Id: I1aadea6c7fd0183715c9eaa77e2551e6d0607795
    Signed-off-by: Tomi Juvonen <tomi.juvonen@nokia.com>

diff --git a/docs/submodules/doctor b/docs/submodules/doctor
index 825a0a0..3ddc239 160000 (submodule)
--- a/docs/submodules/doctor
+++ b/docs/submodules/doctor
@@ -1 +1 @@
-Subproject commit 825a0a0dd5e8028129b782ed21c549586257b1c5
+Subproject commit 3ddc2392b0ed364eede49ff006d64df3ea456350