Eliminate questionable syntax for stdin redirection. This probably also speeds things up a bit.

llvm-svn: 51357
diff --git a/llvm/test/ExecutionEngine/test-ret.ll b/llvm/test/ExecutionEngine/test-ret.ll
index 2d79945..e684fd5 100644
--- a/llvm/test/ExecutionEngine/test-ret.ll
+++ b/llvm/test/ExecutionEngine/test-ret.ll
@@ -1,4 +1,4 @@
-; RUN: llvm-as < %s -f -o %t.bc
+; RUN: llvm-as %s -f -o %t.bc
 ; RUN: lli %t.bc > /dev/null
 
 ; test return instructions