2.remove duplicated typedef. git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9086 6f19259b-4bc3-4df7-8a09-765794883524
2. refine comments in Ip4.h and Tcp4.h. git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9081 6f19259b-4bc3-4df7-8a09-765794883524