Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ModuleID

This is done to avoid odd test failures, like the one fixed in r171243.

llvm-svn: 173163
diff --git a/llvm/test/Transforms/ObjCARC/ensure-that-exception-unwind-path-is-visited.ll b/llvm/test/Transforms/ObjCARC/ensure-that-exception-unwind-path-is-visited.ll
index 0c30634..1fd03e7 100644
--- a/llvm/test/Transforms/ObjCARC/ensure-that-exception-unwind-path-is-visited.ll
+++ b/llvm/test/Transforms/ObjCARC/ensure-that-exception-unwind-path-is-visited.ll
@@ -1,4 +1,4 @@
-; RUN: opt -objc-arc -S %s | FileCheck %s
+; RUN: opt -objc-arc -S < %s | FileCheck %s
 ; rdar://11744105
 ; bugzilla://14584