unittest: fix MakeLocalWithDeclVar test

The module dump may contain a declaration of the lifetime.start
instrinsic. Maybe it didn't before, but it does now after I
update LLVM.

Count actual calls to lifetime.start, not only the function name.
So it doesn't match the declaration.

Change-Id: I7ab8414127c9ee3b6042291d2b3bc83f988895bb
Reviewed-on: https://go-review.googlesource.com/c/gollvm/+/168400
Reviewed-by: Than McIntosh <thanm@google.com>
diff --git a/unittests/BackendCore/BackendVarTests.cpp b/unittests/BackendCore/BackendVarTests.cpp
index 237b1cf..183a0ae 100644
--- a/unittests/BackendCore/BackendVarTests.cpp
+++ b/unittests/BackendCore/BackendVarTests.cpp
@@ -724,7 +724,7 @@
 
   // Expect to see only one lifetime start, since A) loc1 is at the top
   // level, and B) loc2 uses loc1 as declVar.
-  const char *expected = "@llvm.lifetime.start.p0i8(i64";
+  const char *expected = "call void @llvm.lifetime.start.p0i8(i64";
   EXPECT_EQ(h.countInstancesInModuleDump(expected), 1u);
 }