Apply suggestions from code review

Co-authored-by: Gordon Brown <[email protected]>

adoc/chapters/programming_interface.adoc

@@ -17841,7 +17841,7 @@ _Constraints:_ These functions have the same constraints as the equivalent
 member functions of the [code]#vec# class.
 
 _Effects:_ The effect of these functions is the same as if they were called on
-a temporary [code]#vec# object that contains the result of the swizzle
+a temporary [code]#vec# object that contains the result of the captured swizzle
 operation.
 
 '''