Un-XFAIL obj-recursion.rs for rustc.

Author: graydon

src/Makefile

@@ -440,6 +440,7 @@ TEST_XFAILS_RUSTC := $(filter-out \
                         lazy-init.rs \
                         lazy-and-or.rs \
                         multiline-comment.rs \
+                        obj-recursion.rs \
                         operator-associativity.rs \
                         output-slot-variants.rs \
                         readalias.rs \