UnitTests: Followup to 305519

We have to use ASSERT_XXX instead of EXPECT_XXX if the test cannot
continue in the failure case.

llvm-svn: 305522
diff --git a/llvm/unittests/MI/LiveIntervalTest.cpp b/llvm/unittests/MI/LiveIntervalTest.cpp
index 43dfa4a..01dce37 100644
--- a/llvm/unittests/MI/LiveIntervalTest.cpp
+++ b/llvm/unittests/MI/LiveIntervalTest.cpp
@@ -151,7 +151,7 @@
   std::unique_ptr<MIRParser> MIR;
   std::unique_ptr<Module> M = parseMIR(Context, PM, MIR, *TM, MIRString,
                                        "func");
-  EXPECT_TRUE(M);
+  ASSERT_TRUE(M);
 
   PM.add(new TestPass(T));