openflow_input: change gentable delete error case
It's easier for the controller if deleting a nonexistent entry is not an error.
diff --git a/openflow_input/bsn_gentable b/openflow_input/bsn_gentable
index 674d298..6500789 100644
--- a/openflow_input/bsn_gentable
+++ b/openflow_input/bsn_gentable
@@ -96,7 +96,7 @@
//
// If the switch cannot process the message then it should reply with an error
// message. The contents of the table must not be changed in case of an error.
-// If the key does not exist in the table an error message will be generated.
+// If the key does not exist in the table no error will be generated.
struct of_bsn_gentable_entry_delete : of_bsn_header {
uint8_t version;
uint8_t type == 4;