Apply changes to migrate to llvm upstream r135568.

- Remove the const qualifier of llvm::Type and
  llvm::PointerType due to the API change.

- Update the relocation model setup code, since
  llvm::TargetMachine changes the API.

- Qualify dyn_cast with llvm namespace.

Change-Id: I4820fb86effc3a62569e19a6a8753ba9e960f6b2
diff --git a/slang_rs_object_ref_count.cpp b/slang_rs_object_ref_count.cpp
index 131a086..a54fdd0 100644
--- a/slang_rs_object_ref_count.cpp
+++ b/slang_rs_object_ref_count.cpp
@@ -227,7 +227,8 @@
       RSASTReplace R(mCtx);
       R.ReplaceStmt(mOuterStmt, S, CS);
     }
-    clang::CompoundStmt *CS = dyn_cast<clang::CompoundStmt>(mOuterStmt);
+    clang::CompoundStmt *CS =
+      llvm::dyn_cast<clang::CompoundStmt>(mOuterStmt);
     slangAssert(CS);
     if (CS) {
       AppendAfterStmt(mCtx, CS, NULL, mStmtList);