target/s390x: Replace HOST_BIG_ENDIAN #ifdef with if() check

Replace preprocessor-time #ifdef with a compile-time check
to ensure all code paths are built and tested. This reduces
build-time configuration complexity and simplifies code
maintainability.

No functional change intended.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20251010134226.72221-15-philmd@linaro.org>

target/s390x/tcg/translate.c

@@ -258,9 +258,9 @@ static inline int vec_reg_offset(uint8_t reg, uint8_t enr, MemOp es)
      * 16 byte operations to handle it in a special way.
      */
     g_assert(es <= MO_64);
-#if !HOST_BIG_ENDIAN
-    offs ^= (8 - bytes);
-#endif
+    if (!HOST_BIG_ENDIAN) {
+        offs ^= (8 - bytes);
+    }
     return offs + vec_full_reg_offset(reg);
 }
 

target/s390x/tcg/translate_vx.c.inc

@@ -175,9 +175,9 @@ static void get_vec_element_ptr_i64(TCGv_ptr ptr, uint8_t reg, TCGv_i64 enr,
 
     /* convert it to an element offset relative to tcg_env (vec_reg_offset() */
     tcg_gen_shli_i64(tmp, tmp, es);
-#if !HOST_BIG_ENDIAN
-    tcg_gen_xori_i64(tmp, tmp, 8 - NUM_VEC_ELEMENT_BYTES(es));
-#endif
+    if (!HOST_BIG_ENDIAN) {
+        tcg_gen_xori_i64(tmp, tmp, 8 - NUM_VEC_ELEMENT_BYTES(es));
+    }
     tcg_gen_addi_i64(tmp, tmp, vec_full_reg_offset(reg));
 
     /* generate the final ptr by adding tcg_env */