8349751: AIX build failure after upgrade pipewire to 1.3.81

Backport-of: 19c0ce43e258d00d77314d76a361feb2069a5af1

Author: GoeLin

src/java.desktop/unix/native/libpipewire/include/spa/utils/endian.h

@@ -18,6 +18,10 @@
 #define bswap_16 _byteswap_ushort
 #define bswap_32 _byteswap_ulong
 #define bswap_64 _byteswap_uint64
+#elif defined(AIX)
+#include <sys/machine.h>
+#define __BIG_ENDIAN      BIG_ENDIAN
+#define __BYTE_ORDER      BIG_ENDIAN
 #else
 #include <endian.h>
 #include <byteswap.h>