Make port remove a request/reply pair.

Also added status indicator for create reply.

Updated c check build a bit to add flags
diff --git a/openflow_input/bsn_vport b/openflow_input/bsn_vport
index cb197dd..476527a 100644
--- a/openflow_input/bsn_vport
+++ b/openflow_input/bsn_vport
@@ -80,11 +80,12 @@
     uint32_t xid;           // Must match create_request
     uint32_t experimenter == 0x5c16c7;
     uint32_t subtype == 16;
+    uint32_t status;        // 0 means success
     uint32_t vport_no;      // The OF port number created.  16-bits for OF 1.0
 };
 
 // Request from controller to switch to remove a vport
-struct of_bsn_virtual_port_remove {
+struct of_bsn_virtual_port_remove_request {
     uint8_t version;
     uint8_t type == 4;
     uint16_t length;
@@ -93,3 +94,14 @@
     uint32_t subtype == 17;
     uint32_t vport_no;      // The OF port number to be removed
 };
+
+// Request from controller to switch to remove a vport
+struct of_bsn_virtual_port_remove_reply {
+    uint8_t version;
+    uint8_t type == 4;
+    uint16_t length;
+    uint32_t xid;           // Must match request xid
+    uint32_t experimenter == 0x5c16c7;
+    uint32_t subtype == 26;
+    uint32_t status;        // 0 means success
+};