DebugInfo: Drop rest of DIDescriptor subclasses

Delete the remaining subclasses of (the already deleted) `DIDescriptor`.
Part of PR23080.

llvm-svn: 235404
diff --git a/llvm/unittests/Transforms/Utils/Cloning.cpp b/llvm/unittests/Transforms/Utils/Cloning.cpp
index d778903..35bdd36 100644
--- a/llvm/unittests/Transforms/Utils/Cloning.cpp
+++ b/llvm/unittests/Transforms/Utils/Cloning.cpp
@@ -254,9 +254,9 @@
     // Create a local variable around the alloca
     auto *IntType =
         DBuilder.createBasicType("int", 32, 0, dwarf::DW_ATE_signed);
-    DIExpression E = DBuilder.createExpression();
-    DIVariable Variable = DBuilder.createLocalVariable(
-      dwarf::DW_TAG_auto_variable, Subprogram, "x", File, 5, IntType, true);
+    auto *E = DBuilder.createExpression();
+    auto *Variable = DBuilder.createLocalVariable(
+        dwarf::DW_TAG_auto_variable, Subprogram, "x", File, 5, IntType, true);
     auto *DL = MDLocation::get(Subprogram->getContext(), 5, 0, Subprogram);
     DBuilder.insertDeclare(Alloca, Variable, E, DL, Store);
     DBuilder.insertDbgValueIntrinsic(AllocaContent, 0, Variable, E, DL,