Add transaction support to Set Lan Cmd and Set Channel Access Cmd

* Ipmid will cache single setting to memory by Set Lan cmd
* Add Set Channel Access cmd to ipmid
* Set Channel Access cmd is used to apply the previous cached settings

TODO: parse the request data of Set Channel Access cmd if needed.

Resolves openbmc/openbmc#444

Change-Id: Ia7ac57a551731920ffe69dad5c69c995521fed02
Signed-off-by: Nan Li <william.bjlinan@hotmail.com>
diff --git a/apphandler.h b/apphandler.h
index f59e315..5753c27 100644
--- a/apphandler.h
+++ b/apphandler.h
@@ -28,6 +28,7 @@
     IPMI_CMD_GET_MSG_FLAGS          = 0x31,
     IPMI_CMD_READ_EVENT             = 0x35,
     IPMI_CMD_GET_CAP_BIT            = 0x36,
+    IPMI_CMD_SET_CHAN_ACCESS        = 0x40,
     IPMI_CMD_GET_CHAN_INFO          = 0x42,
 
 };