libpldm: add enum used by some Network Controller

The network interface connectors and ports connection entity types
(along with Link State set and Redfish Device Resource PDR) are useful
for some NIC devices.

Change-Id: I28cd2c9db4ef3bfc9885892b41312d31a709ebbf
Signed-off-by: Jinliang Wang <jinliangw@google.com>
diff --git a/include/libpldm/state_set.h b/include/libpldm/state_set.h
index 8e86529..a64cf83 100644
--- a/include/libpldm/state_set.h
+++ b/include/libpldm/state_set.h
@@ -189,6 +189,13 @@
 	PLDM_STATE_SET_THERMAL_TRIP_STATUS_THERMAL_TRIP = 2,
 };
 
+/* @brief List of states for the Set Link state (ID 33).
+ */
+enum pldm_state_set_link_state_values {
+	PLDM_STATE_SET_LINK_STATE_CONNECTED = 1,
+	PLDM_STATE_SET_LINK_STATE_DISCONNECTED = 2,
+};
+
 /* @brief List of states for the Software-related state set (ID 129).
  */
 enum pldm_software_termination_status_values {