apply issue/#13952 fix to SDL_cpuinfo.h, too.

include/SDL_cpuinfo.h

@@ -39,21 +39,19 @@
 /* Need to do this here because intrin.h has C++ code in it */
 /* Visual Studio 2005 has a bug where intrin.h conflicts with winnt.h */
 #if defined(_MSC_VER) && (_MSC_VER >= 1500) && (defined(_M_IX86) || defined(_M_X64))
-#ifdef __clang__
 /* As of Clang 11, '_m_prefetchw' is conflicting with the winnt.h's version,
    so we define the needed '_m_prefetch' here as a pseudo-header, until the issue is fixed. */
-
+#if defined(__clang__) &&  !_SDL_HAS_BUILTIN(_m_prefetch)
 #ifndef __PRFCHWINTRIN_H
 #define __PRFCHWINTRIN_H
-
 static __inline__ void __attribute__((__always_inline__, __nodebug__))
 _m_prefetch(void *__P)
 {
-  __builtin_prefetch (__P, 0, 3 /* _MM_HINT_T0 */);
+  __builtin_prefetch(__P, 0, 3 /* _MM_HINT_T0 */);
 }
-
 #endif /* __PRFCHWINTRIN_H */
 #endif /* __clang__ */
+
 #include <intrin.h>
 #ifndef _WIN64
 #ifndef __MMX__