f cfg-remove unsupported state

Author: TheBlueMatt

lightning/src/sync/mod.rs

@@ -3,6 +3,7 @@
 pub(crate) enum LockHeldState {
 	HeldByThread,
 	NotHeldByThread,
+	#[cfg(any(feature = "_bench_unstable", not(test)))]
 	Unsupported,
 }