[metadata] Skip symbol name mangling on non-Windows for netcore (#33940)

Fixes #33246

Author: CoffeeFlux

src/mono/mono/metadata/native-library.c

@@ -1296,6 +1296,7 @@ pinvoke_probe_for_symbol (MonoDl *module, MonoMethodPInvoke *piinfo, const char
 mono_trace (G_LOG_LEVEL_DEBUG, MONO_TRACE_DLLIMPORT,
 "Searching for '%s'.", import);
 
+#if !defined(ENABLE_NETCORE) || defined(HOST_WIN32) // For netcore, name mangling is Windows-exclusive
 if (piinfo->piflags & PINVOKE_ATTRIBUTE_NO_MANGLE)
 error_msg = mono_dl_symbol (module, import, &addr);
 else {
@@ -1380,6 +1381,9 @@ pinvoke_probe_for_symbol (MonoDl *module, MonoMethodPInvoke *piinfo, const char
 }
 }
 }
+#else
+error_msg = mono_dl_symbol (module, import, &addr);
+#endif
 
 *error_msg_out = error_msg;
 return addr;