update submodule to v1.16

Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>

diff --git a/upstream b/upstream
index 0ba5985c3ddec8429b989f0e7bd3324f53e0a9b0..dfd50f0c7a16f5c9c6323e4ef960f859a46b8de8 160000 (submodule)
--- a/upstream
+++ b/upstream
@@ -1 +1 @@
-Subproject commit 0ba5985c3ddec8429b989f0e7bd3324f53e0a9b0
+Subproject commit dfd50f0c7a16f5c9c6323e4ef960f859a46b8de8