refactor code for the packet, get rid of packet_impl.hh

and call it packet_access.hh and fix the #includes so
things compile right.

--HG--
extra : convert_revision : d3626c9715b9f7e51bb3ab8d97e971fad4e0b724

src/mem/cache/base_cache.cc

@@ -33,11 +33,10 @@
  * Definition of BaseCache functions.
  */
 
+#include "cpu/base.hh"
+#include "cpu/smt.hh"
 #include "mem/cache/base_cache.hh"
 #include "mem/cache/miss/mshr.hh"
-#include "mem/packet_impl.hh"
-#include "cpu/smt.hh"
-#include "cpu/base.hh"
 
 using namespace std;