Weaken note about no-op from "is" to "may be"

adoc/extensions/sycl_khr_free_function_commands.adoc

@@ -768,7 +768,7 @@ Any commands submitted after this barrier cannot begin execution until:
 
 {note}If a [code]#command_barrier# is submitted to an in-order queue and has no
 other dependencies (e.g., specified by [code]#handler::depends_on#), then this
-operation is a no-op.{endnote}
+operation may be a no-op.{endnote}
 
 '''
 
@@ -792,6 +792,6 @@ Any commands submitted after this barrier cannot begin execution until:
 
 {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#), then this
-operation is a no-op.{endnote}
+operation may be a no-op.{endnote}
 
 '''