Un-XFAILing spawn tests.

src/test/run-pass/spawn.rs

@@ -1,6 +1,4 @@
 // xfail-stage0
-// xfail-stage1
-// xfail-stage2
 // -*- rust -*-
 
 fn main() {

src/test/run-pass/spawn2.rs

@@ -1,10 +1,6 @@
 // xfail-stage0
-// xfail-stage1
-// xfail-stage2
 // -*- rust -*-
 
-use std;
-
 fn main() {
   spawn child(10, 20);
 }