[SYCL][Graph] Fix unannotated fall-through between switch labels (#9966)

Together with [PR#9949](#9949):
Fix post-commit failures after
[PR#9728](#9728)

Author: reble

sycl/source/detail/graph_impl.hpp

@@ -125,6 +125,7 @@ class node_impl {
       return createCGCopy<sycl::detail::CGExecKernel>();
     case sycl::detail::CG::CodeplayInteropTask:
       assert(false);
+      break;
     // TODO: Uncomment this once we implement support for interop task so we can
     // test required changes to the CG class.
 
@@ -153,6 +154,7 @@ class node_impl {
       return createCGCopy<sycl::detail::CGMemset2DUSM>();
     case sycl::detail::CG::CodeplayHostTask:
       assert(false);
+      break;
       // TODO: Uncomment this once we implement support for host task so we can
       // test required changes to the CG class.