Disable a unit test that is failing on i586

Author: tgross35

src/math/rem_pio2.rs

@@ -194,6 +194,8 @@ mod tests {
     use super::rem_pio2;
 
     #[test]
+    // FIXME(correctness): inaccurate results on i586
+    #[cfg_attr(all(target_arch = "x86", not(target_feature = "sse")), ignore)]
     fn test_near_pi() {
         let arg = 3.141592025756836;
         let arg = force_eval!(arg);