native: Don't use __xstat on loongarch64

We currently define __xstat to allow linking against older glibc builds.

glibc on loongarch64 does not have __xstat (not necessary), which
currently breaks our native library.

Detect the loongarch architecture and skip our xstat workaround.

Also see https://lists.openembedded.org/g/openembedded-core/topic/99216091

junixsocket-native/src/main/c/config.h

@@ -367,20 +367,24 @@ int jux_mangleErrno(int);
 # else
 // This allows us to link against older glibc versions
 # define memcpy memmove
-# ifndef _STAT_VER
+# if defined(__loongarch64)
+// no stat/__xstat workaround on loongarch64
+# else
+# ifndef _STAT_VER
 # if defined(__aarch64__) || defined(__riscv)
 # define _STAT_VER 0
 # elif defined(__x86_64__)
 # define _STAT_VER 1
 # else
 # define _STAT_VER 3
 # endif
-# endif
-# if !defined(__xstat)
+#  endif
+#  if !defined(__xstat)
 extern int __xstat (int __ver, const char *__filename,
  struct stat *__stat_buf) __THROW __nonnull ((2, 3));
+# endif
+# define stat(...) __xstat(_STAT_VER, __VA_ARGS__)
 # endif
-# define stat(...) __xstat(_STAT_VER, __VA_ARGS__)
 # endif
 #endif