std: Remove unstable from ReentrantMutex

This isn't exported so it doesn't need a tag.

diff --git a/src/libstd/sys/common/remutex.rs b/src/libstd/sys/common/remutex.rs
index 2e2be63c3cb5b300ea63c813cc8951e74acc53a9..1793ad0e4459f842e4cbd3b33e9cadcdfb4abf79 100644 (file)
--- a/src/libstd/sys/common/remutex.rs
+++ b/src/libstd/sys/common/remutex.rs
@@ -8,9 +8,6 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
-#![unstable(feature = "reentrant_mutex", reason = "new API",
-            issue = "27738")]
-
 use prelude::v1::*;
 
 use fmt;