Add always_inline to string move constructors

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@124252 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/string b/include/string
index 469e3dd..b3bc58e 100644
--- a/include/string
+++ b/include/string
@@ -1033,7 +1033,9 @@
     basic_string(const basic_string& __str);
     basic_string(const basic_string& __str, const allocator_type& __a);
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
+    _LIBCPP_INLINE_VISIBILITY
     basic_string(basic_string&& __str);
+    _LIBCPP_INLINE_VISIBILITY
     basic_string(basic_string&& __str, const allocator_type& __a);
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
     _LIBCPP_INLINE_VISIBILITY basic_string(const_pointer __s);