Add RFC4039 rapid commit support.
diff --git a/src/dhcp-protocol.h b/src/dhcp-protocol.h
index a4a3535..389c85e 100644
--- a/src/dhcp-protocol.h
+++ b/src/dhcp-protocol.h
@@ -54,6 +54,7 @@
 #define OPTION_SNAME             66
 #define OPTION_FILENAME          67
 #define OPTION_USER_CLASS        77
+#define OPTION_RAPID_COMMIT      80
 #define OPTION_CLIENT_FQDN       81
 #define OPTION_AGENT_ID          82
 #define OPTION_ARCH              93