[OpenCL] Fix semantic check of ndrange_t for device_side_enqueue.

Check unqualified type for ndrange argument in device_side_enqueue so
device_side_enqueue accept const and volatile qualified ndranges.

Differential Revision: https://reviews.llvm.org/D31458

Patch by Dmitry Borisenkov!

llvm-svn: 300988
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index 45523b3..044ec74 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -408,7 +408,7 @@
   }
 
   // Third argument is always an ndrange_t type.
-  if (Arg2->getType().getAsString() != "ndrange_t") {
+  if (Arg2->getType().getUnqualifiedType().getAsString() != "ndrange_t") {
     S.Diag(TheCall->getArg(2)->getLocStart(),
            diag::err_opencl_enqueue_kernel_expected_type)
         << "'ndrange_t'";