target: Remove unnecessary CPU() cast

The CPU() macro is defined as:

  #define CPU(obj) ((CPUState *)(obj))

which expands to:

  ((CPUState *)object_dynamic_cast_assert((Object *)(obj), (name),
                                          __FILE__, __LINE__, __func__))

This assertion can only fail when @obj points to something other
than its stated type, i.e. when we're in undefined behavior country.

Remove the unnecessary CPU() casts when we already know the pointer
is of CPUState type.

Patch created mechanically using spatch with this script:

  @@
  typedef CPUState;
  CPUState *s;
  @@
  -   CPU(s)
  +   s

Acked-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200512070020.22782-2-f4bug@amsat.org>

target/ppc/mmu_helper.c

@@ -1820,7 +1820,7 @@ static inline void do_invalidate_BAT(CPUPPCState *env, target_ulong BATu,
     if (((end - base) >> TARGET_PAGE_BITS) > 1024) {
         /* Flushing 1024 4K pages is slower than a complete flush */
         LOG_BATS("Flush all BATs\n");
-        tlb_flush(CPU(cs));
+        tlb_flush(cs);
         LOG_BATS("Flush done\n");
         return;
     }