pidof: rename test & remove target_os cfg

Author: cakebaker

tests/by-util/test_pidof.rs

@@ -5,6 +5,11 @@
 
 use crate::common::util::TestScenario;
 
+#[test]
+fn test_no_args() {
+    new_ucmd!().fails().code_is(1).no_output();
+}
+
 #[test]
 fn test_invalid_arg() {
     new_ucmd!().arg("--definitely-invalid").fails().code_is(1);
@@ -23,12 +28,6 @@ fn test_find_kthreadd() {
     new_ucmd!().arg("kthreadd").succeeds();
 }
 
-#[test]
-#[cfg(target_os = "linux")]
-fn test_no_program() {
-    new_ucmd!().fails().code_is(1).no_output();
-}
-
 #[test]
 #[cfg(target_os = "linux")]
 fn test_no_pid_found() {