Add sycl_khr_free_function_commands extension

adoc/chapters/architecture.adoc

@@ -1978,6 +1978,7 @@ always matches the byte order of the devices.
 This allows data to be copied between the host and the devices without any byte
 swapping.
 
+[[subsec:example.sycl.application]]
 == Example SYCL application
 
 Below is a more complex example application, combining some of the features

adoc/extensions/index.adoc

@@ -10,4 +10,6 @@ specification, but their design is subject to change.
 // leveloffset=2 allows extensions to be written as standalone documents
 // include::sycl_khr_extension_name.adoc[leveloffset=2]
 
+
 include::sycl_khr_default_context.adoc[leveloffset=2]
+include::sycl_khr_free_function_commands.adoc[leveloffset=2]