don't test for the absence of BAR in the rmake test

it's not related to this feature

Author: Jorge Aparicio

src/test/run-make/used/Makefile

@@ -8,5 +8,4 @@ else
 all:
 	$(RUSTC) -C opt-level=3 --emit=obj used.rs
 	nm -C $(TMPDIR)/used.o | grep FOO
-	nm -C $(TMPDIR)/used.o | grep -v BAR
 endif