Update xvm-prodconfig to version 1.1.50

Requested by glasgall/root@ATHENA.MIT.EDU

diff --git a/xvm-prodconfig b/xvm-prodconfig
index 6e2f3b0..bc54920 160000 (submodule)
--- a/xvm-prodconfig
+++ b/xvm-prodconfig
@@ -1 +1 @@
-Subproject commit 6e2f3b01c04df10c75db2b91808b295b5d48a0e4
+Subproject commit bc54920800b106e5d3c967565a53278fa8da0c45