Disable the libc::personality doc test on QEMU

It's failing there with EPERM.  It's probably seccomp's fault

Author: asomers

src/sys/personality.rs

@@ -78,10 +78,10 @@ pub fn get() -> Result<Persona> {
 ///
 /// Example:
 ///
-// Disable test on aarch64 until we know why it fails.
+// Disable test on aarch64 and with QEMU.  seccomp interference is suspected.
 // https://github.com/nix-rust/nix/issues/2060
-#[cfg_attr(target_arch = "aarch64", doc = " ```no_run")]
-#[cfg_attr(not(target_arch = "aarch64"), doc = " ```")]
+#[cfg_attr(any(qemu, target_arch = "aarch64"), doc = " ```no_run")]
+#[cfg_attr(not(any(qemu, target_arch = "aarch64")), doc = " ```")]
 /// # use nix::sys::personality::{self, Persona};
 /// let mut pers = personality::get().unwrap();
 /// assert!(!pers.contains(Persona::ADDR_NO_RANDOMIZE));