Fix typo in non-normative note

adoc/extensions/sycl_khr_free_function_commands.adoc

@@ -839,7 +839,7 @@ commands associated with [code]#events# (and any commands associated with other
 dependent events) have completed.
 
 {note}For both overloads, if [code]#events# is empty and an event barrier has no
-other dependencies (e.g., specified by [code]#handler::depends_on#), it is ot
+other dependencies (e.g., specified by [code]#handler::depends_on#), it is not
 required to wait for any commands unless the [code]#queue# is in-order.{endnote}
 
 '''