block coerce_pointee_validated for stabilization

Author: dingxiangfei2009

core/src/marker.rs

@@ -1299,7 +1299,7 @@ pub macro CoercePointee($item:item) {
 /// and shall not ever be stabilised.
 #[cfg(not(bootstrap))]
 #[lang = "coerce_pointee_validated"]
-#[unstable(feature = "coerce_pointee_validated", issue = "123430")]
+#[unstable(feature = "coerce_pointee_validated", issue = "none")]
 #[doc(hidden)]
 pub trait CoercePointeeValidated {
     /* compiler built-in */