system: Allow restricting the legacy ld/st_phys() 'native-endian' API

Guard the native endian APIs we want to remove by surrounding
them with TARGET_NOT_USING_LEGACY_NATIVE_ENDIAN_API #ifdef'ry.

Since all targets can check the definition, do not poison it.

Once a target gets cleaned we'll set the definition in the
target config, then the target won't be able to use the legacy
API anymore.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-ID: <20260109165058.59144-15-philmd@linaro.org>

include/system/memory_ldst_phys.h.inc

@@ -31,8 +31,10 @@ static inline void glue(stb_phys, SUFFIX)(ARG1_DECL, hwaddr addr, uint8_t val)
                                     MEMTXATTRS_UNSPECIFIED, NULL);
 }
 
+#ifndef TARGET_NOT_USING_LEGACY_NATIVE_ENDIAN_API
 #define ENDIANNESS
 #include "system/memory_ldst_phys_endian.h.inc"
+#endif /* TARGET_NOT_USING_LEGACY_NATIVE_ENDIAN_API */
 
 #define ENDIANNESS  _le
 #include "system/memory_ldst_phys_endian.h.inc"

scripts/make-config-poison.sh

@@ -11,6 +11,7 @@ exec sed -n \
   -e '/CONFIG_USER_ONLY/d' \
   -e '/CONFIG_SOFTMMU/d' \
   -e '/TARGET_NOT_USING_LEGACY_LDST_PHYS_API/d' \
+  -e '/TARGET_NOT_USING_LEGACY_NATIVE_ENDIAN_API/d' \
   -e '/^#define / {' \
   -e    's///' \
   -e    's/ .*//' \