Implement LWG 2787 - [file_status.cons] is inconsistent

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@297071 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/experimental/filesystem b/include/experimental/filesystem
index 6ce446f..cf62ca2 100644
--- a/include/experimental/filesystem
+++ b/include/experimental/filesystem
@@ -408,8 +408,10 @@
 public:
     // constructors
     _LIBCPP_INLINE_VISIBILITY
-    explicit file_status(file_type __ft = file_type::none,
-                         perms __prms   = perms::unknown) _NOEXCEPT
+    file_status() _NOEXCEPT : file_status(file_type::none) {}
+    _LIBCPP_INLINE_VISIBILITY
+    explicit file_status(file_type __ft,
+                         perms __prms = perms::unknown) _NOEXCEPT
       : __ft_(__ft), __prms_(__prms)
     {}