Fix test_acct in Cirrus.

It requires CAP_SYS_PACCT

Author: asomers

test/test_unistd.rs

@@ -387,13 +387,30 @@ fn test_lseek64() {
     close(tmpfd).unwrap();
 }
 
+cfg_if!{
+    if #[cfg(any(target_os = "android", target_os = "linux"))] {
+        macro_rules! require_acct{
+            () => {
+                require_capability!(CAP_SYS_PACCT);
+            }
+        }
+    } else {
+        macro_rules! require_acct{
+            () => {
+                skip_if_not_root!("test_acct");
+            }
+        }
+    }
+}
+
 #[test]
 fn test_acct() {
     use tempfile::NamedTempFile;
     use std::process::Command;
     use std::{thread, time};
 
-    skip_if_not_root!("test_acct");
+    require_acct!();
+
     let file = NamedTempFile::new().unwrap();
     let path = file.path().to_str().unwrap();