Only link the tests against -ldl on linux

llvm-svn: 220509

libcxxabi/test/lit.cfg

@@ -227,7 +227,7 @@ san = lit_config.params.get('llvm_use_sanitizer', None)
 if san is None:
     san = getattr(config, 'llvm_use_sanitizer', None)
 if san:
-    if not sys.platform.startswith('freebsd'):
+    if sys.platform == 'linux2':
         link_flags += ['-ldl']
     if san == 'Address':
         compile_flags += ['-fsanitize=address']