benches: revert "properly gate unix benches" (#7412)

This reverts commit 933fa498d0bda193960784cb3f6a47be3bc1e492.

benches/Cargo.toml

@@ -71,12 +71,12 @@ name = "sync_semaphore"
 path = "sync_semaphore.rs"
 harness = false
 
-[[target.'cfg(unix)'.bench]]
+[[bench]]
 name = "signal"
 path = "signal.rs"
 harness = false
 
-[[target.'cfg(unix)'.bench]]
+[[bench]]
 name = "fs"
 path = "fs.rs"
 harness = false

benches/fs.rs

@@ -1,3 +1,5 @@
+#![cfg(unix)]
+
 use tokio_stream::StreamExt;
 
 use tokio::fs::File;

benches/signal.rs

@@ -1,4 +1,5 @@
 //! Benchmark the delay in propagating OS signals to any listeners.
+#![cfg(unix)]
 
 use criterion::{criterion_group, criterion_main, Criterion};
 use std::future::Future;