Add -opaque-pointers option to the LIT test

Author: preethi-intel

llvm/test/Transforms/InstCombine/mul_fold.ll

@@ -1,5 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt < %s -passes=instcombine -S | FileCheck %s
+; RUN: opt < %s -opaque-pointers -passes=instcombine -S | FileCheck %s
 
 declare i8 @use8(i8)
 declare i16 @use16(i16)