add iana header to store OEM Numbers

The iana.hpp header is installed to identify OEM IPMI numbers used, to
avoid namespace conflicts.

Change-Id: Ifd629817e3b921f86a5ea4cf2c2965a44a2d8201
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/host-ipmid/oemrouter.hpp b/host-ipmid/oemrouter.hpp
index d6f0735..fb12750 100644
--- a/host-ipmid/oemrouter.hpp
+++ b/host-ipmid/oemrouter.hpp
@@ -1,18 +1,18 @@
 #pragma once
 
+#include <host-ipmid/ipmid-api.h>
+
 #include <array>
 #include <cstdint>
 #include <functional>
+#include <host-ipmid/iana.hpp>
 #include <vector>
 
-#include "host-ipmid/ipmid-api.h"
-
 namespace oem
 {
 constexpr size_t groupMagicSize = 3;
 
 using Group = std::array<uint8_t, groupMagicSize>;
-using Number = uint32_t; // smallest standard size >= 24.
 
 // Handler signature includes ipmi cmd to support wildcard cmd match.
 // Buffers and lengths exclude the OemGroup bytes in the IPMI message.