SEBA-420 remove superfluous xproto options

Change-Id: I15f22529034a209ec761ef8fed7145e185e9dd47
diff --git a/xos/synchronizer/models/fabric-crossconnect.xproto b/xos/synchronizer/models/fabric-crossconnect.xproto
index 3290495..d908092 100644
--- a/xos/synchronizer/models/fabric-crossconnect.xproto
+++ b/xos/synchronizer/models/fabric-crossconnect.xproto
@@ -25,14 +25,8 @@
 message BNGPortMapping (XOSBase) {
     required string s_tag = 1 [
         help_text = "Single s-tag, range of s-tags, or 'ANY'",
-        blank = False,
-        db_index = False,
-        null = False,
         tosca_key = True,
         unique = True];
     required int32 switch_port = 2 [
-        help_text = "Switch port where BNG or other egress point is connected",
-        blank = False,
-        db_index = False,
-        null = False];
+        help_text = "Switch port where BNG or other egress point is connected"];
 }