Simple renaming: CPUOldState -> CPUArchState where relevant.

This patch changes a few headers and sources to match upstream when
distinguishing between CPUArchState and CPUOldState (which will become
CPUState soon). For now, both types are identical so this should not
change the generated binaries at all.

Change-Id: I738b4ccaf75838a5931538dd52d1873750f1b816
diff --git a/cputlb.c b/cputlb.c
index d17f324..2e21e0b 100644
--- a/cputlb.c
+++ b/cputlb.c
@@ -152,7 +152,7 @@
    is permitted. Return 0 if OK or 2 if the page could not be mapped
    (can only happen in non SOFTMMU mode for I/O pages or pages
    conflicting with the host address space). */
-int tlb_set_page_exec(CPUOldState *env, target_ulong vaddr,
+int tlb_set_page_exec(CPUArchState *env, target_ulong vaddr,
                       hwaddr paddr, int prot,
                       int mmu_idx, int is_softmmu)
 {