[SYCL][Doc] Fix work_group_scratch_memory example

The example in the specification was using an old API that we removed
in intel#14785.  Update the example and the spec wording to use
`launch_config` from sycl_ext_oneapi_enqueue_functions to pass the
property with the size of the scratch memory.

Author: gmlueck

sycl/doc/extensions/experimental/sycl_ext_oneapi_work_group_scratch_memory.asciidoc

@@ -43,8 +43,7 @@ SYCL specification refer to that revision.
 The following extensions are required:
 
 - link:../experimental/sycl_ext_oneapi_properties.asciidoc[sycl_ext_oneapi_properties]
-
-- link:../experimental/sycl_ext_oneapi_kernel_properties.asciidoc[sycl_ext_oneapi_kernel_properties]
+- link:../experimental/sycl_ext_oneapi_enqueue_functions.asciidoc[sycl_ext_oneapi_enqueue_functions]
 
 
 == Status
@@ -112,9 +111,9 @@ in device local memory.
 
 === Kernel properties
 
-The `work_group_scratch_size` property must be passed to a kernel to determine
-the run-time size of the device local memory allocation associated with
-all `get_work_group_scratch_memory` calls.
+The `work_group_scratch_size` property must be passed as a kernel launch
+property to determine the run-time size of the device local memory allocation
+associated with all `get_work_group_scratch_memory` calls.
 
 [source,c++]
 ----
@@ -151,38 +150,33 @@ then the implementation must throw a synchronous exception with the
 local memory into account, whether via the `work_group_scratch_size` property
 or other APIs such as `local_accessor`.
 
+
 == Example
 
 [source,c++]
 ----
+#include <sycl/sycl.hpp>
 namespace syclex = sycl::ext::oneapi::experimental;
 
-...
-
-q.parallel_for(sycl::nd_range<1>{N, M},
-  syclex::properties{syclex::work_group_scratch_size(M * sizeof(int))},
-  [=](sycl::nd_item<1> it) {
- auto ptr = syclex::get_work_group_scratch_memory();
- auto ptr2 = syclex::get_work_group_scratch_memory();
-});
-----
-
+constexpr size_t GLOBAL = 1024;
+constexpr size_t N = 256;
 
-== Implementation notes
+int main() {
+  sycl::queue q;
 
-This non-normative section provides information about one possible
-implementation of this extension.  It is not part of the specification of the
-extension's API.
+  syclex::launch_config cfg{
+    sycl::nd_range{{GLOBAL}, {N}},
+    syclex::properties{
+      syclex::work_group_scratch_size{N * sizeof(int)}
+    }
+  };
 
-For `get_work_group_scratch_memory`,
-the implementation may need to generate some additional code to
-appropriately initialize the pointer(s) returned by the call.
-Alternatively, it may be possible to initialize the pointer to the beginning
-of the device's local memory region (if that value is known). Either way, the
-implementation must account for the existence of one or more `local_accessor`
-objects (which themselves may allocate a dynamic amount of device local
-memory).
-
-
-== Issues
+  syclex::nd_launch(q, cfg, [=](sycl::nd_item<> it) {
+    // Gets a pointer to N int's
+    int *ptr = static_cast<int *>(syclex::get_work_group_scratch_memory());
 
+    // Gets the same pointer to N int's
+    int *ptr2 = static_cast<int *>(syclex::get_work_group_scratch_memory());
+  });
+}
+----