Update git submodules

* Update docs/submodules/functest from branch 'master'
  - Add UEFI image extra properties for CentOS image for aarch64

    Add extra properties for CentOS image when using aarch64
    architecture with UEFI boot mode

    Signed-off-by: Delia Popescu <delia.popescu@enea.com>
    Change-Id: Ie8aa7482627cbb3c31c6c72a31a0e37e86a409c4

diff --git a/docs/submodules/functest b/docs/submodules/functest
index 01d6ded..a6e9a6f 160000 (submodule)
--- a/docs/submodules/functest
+++ b/docs/submodules/functest
@@ -1 +1 @@
-Subproject commit 01d6dedb29f33eaf1024323eccfe50e86c6658b2
+Subproject commit a6e9a6fa2da17f84de91d2d47cb8ccb7e66a8836