system: skip trying to set the locale on NetBSD

Just treat it the same as the other BSDs.

Fixes bitcoin#17379.

Github-Pull: bitcoin#22390
Rebased-From: fdd7144

src/util/system.cpp

@@ -1301,7 +1301,7 @@ void SetupEnvironment()
 #endif
     // On most POSIX systems (e.g. Linux, but not BSD) the environment's locale
     // may be invalid, in which case the "C.UTF-8" locale is used as fallback.
-#if !defined(WIN32) && !defined(MAC_OSX) && !defined(__FreeBSD__) && !defined(__OpenBSD__)
+#if !defined(WIN32) && !defined(MAC_OSX) && !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
     try {
         std::locale(""); // Raises a runtime error if current locale is invalid
     } catch (const std::runtime_error&) {