2. Use ZeroMem to replace gBS->SetMem;
3. Remove marked code;
4. Add IsHub judgement in UsbPortReset function to following EFI1.1 spec;
5. Add brackets for macro definition
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@1740 6f19259b-4bc3-4df7-8a09-765794883524