edk2: update to git snapshot

Want pick up edk2 commit cee7ba349c0c ("ArmVirtQemu: Allow
EFI memory attributes protocol to be disabled").  Needed to
fix issue #1990.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
(cherry picked from commit c3667412582cdda42b36418bed135db96005bb85)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

diff --git a/roms/edk2 b/roms/edk2
index 819cfc6b42a68790a23509e4fcc58ceb70e1965e..b8a3eec88cc74bbfe7fb389d026cc7d1d8a989c8 160000 (submodule)
--- a/roms/edk2
+++ b/roms/edk2
@@ -1 +1 @@
-Subproject commit 819cfc6b42a68790a23509e4fcc58ceb70e1965e
+Subproject commit b8a3eec88cc74bbfe7fb389d026cc7d1d8a989c8