Update git submodules

* Update docs/submodules/apex from branch 'stable/euphrates'
  - Pass flags to allow domain undefine with NVRAM

    Change-Id: I8365dd327d4bf7abebc72922e030b3049cd66de9
    Signed-off-by: Dan Radez <dradez@redhat.com>
    (cherry picked from commit 30c7c9e4de1bbd4d4cdc6f0c775d52f80a3103fb)

diff --git a/docs/submodules/apex b/docs/submodules/apex
index 189b69a..8c9675c 160000 (submodule)
--- a/docs/submodules/apex
+++ b/docs/submodules/apex
@@ -1 +1 @@
-Subproject commit 189b69a875d3eefca2a7eb3fa354b9f4930cbcd7
+Subproject commit 8c9675c16e4350aa855c2d2c847fb18eed3a72ec