Merge pull request #19973 from vhbit/ios-no-copy

iOS: fallout of `marker::NoCopy` removal

Reviewed-by: japaric

Author: bors

src/libstd/rand/os.rs

@@ -170,7 +170,6 @@ mod imp {
     extern crate libc;
 
     use io::{IoResult};
-    use kinds::marker;
     use mem;
     use os;
     use rand::Rng;