Remove duplicate definition of EFI_PEI_CPU_IO_PPI.
Previous definition was in
edk2\EdkCompatibilityPkg\Foundation\Framework\Include\PeiApi.h
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5273 6f19259b-4bc3-4df7-8a09-765794883524