[temp.variadic] Clarify template parameter packs not introduced by pack expansions.

Author: jensmaurer

source/templates.tex

@@ -2816,8 +2816,7 @@
 a \grammarterm{typedef-name}
 (for a type template parameter pack declared without \tcode{template}), or
 a \grammarterm{template-name}
-(for a type template parameter pack declared with \tcode{template})
-if the pack was introduced by a pack expansion,
+(for a type template parameter pack declared with \tcode{template}),
 designating the $i^\text{th}$ corresponding type or value template argument;
 
 \item