exec/cpu: Extract page-protection definitions to page-protection.h

Extract page-protection definitions from "exec/cpu-all.h"
to "exec/page-protection.h".

The list of files requiring the new header was generated
using:

$ git grep -wE \
  'PAGE_(READ|WRITE|EXEC|RWX|VALID|ANON|RESERVED|TARGET_.|PASSTHROUGH)'

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20240427155714.53669-3-philmd@linaro.org>

hw/ppc/sam460ex.c

@@ -21,6 +21,7 @@
 #include "kvm_ppc.h"
 #include "sysemu/device_tree.h"
 #include "sysemu/block-backend.h"
+#include "exec/page-protection.h"
 #include "hw/loader.h"
 #include "elf.h"
 #include "exec/memory.h"