Remove now stray comment

src/librustc_driver/lib.rs

@@ -200,13 +200,6 @@ pub fn run<F>(run_compiler: F) -> isize
 }
 
 fn load_backend_from_dylib(path: &Path) -> fn() -> Box<dyn CodegenBackend> {
-    // Note that we're specifically using `open_global_now` here rather than
-    // `open`, namely we want the behavior on Unix of RTLD_GLOBAL and RTLD_NOW,
-    // where NOW means "bind everything right now" because we don't want
-    // surprises later on and RTLD_GLOBAL allows the symbols to be made
-    // available for future dynamic libraries opened. This is currently used by
-    // loading LLVM and then making its symbols available for other dynamic
-    // libraries.
     let lib = DynamicLibrary::open(Some(path)).unwrap_or_else(|err| {
         let err = format!("couldn't load codegen backend {:?}: {:?}", path, err);
         early_error(ErrorOutputType::default(), &err);