[ASan] Fix IRTests/InstructionsTest.UnaryOperator

Fix ASan regression from r374782.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@374808 91177308-0d34-0410-b5e6-96231b3b80d8

unittests/IR/InstructionsTest.cpp

@@ -1128,6 +1128,7 @@ TEST(InstructionsTest, UnaryOperator) {
   EXPECT_FALSE(isa<BinaryOperator>(F));
 
   F->deleteValue();
+  I->deleteValue();
 }
 
 } // end anonymous namespace