[css-easing-2] Fix syntax definition

Author: jakearchibald

css-easing-2/Overview.bs

@@ -133,7 +133,7 @@ The syntax for specifying an [=easing function=] is as follows:
 
 <div class="prod"><dfn type>&lt;easing-function&gt;</dfn> =
   ''linear'' |
-  ''linear()'' |
+  <<linear-easing-function>> |
   <<cubic-bezier-easing-function>> |
   <<step-easing-function>></div>
 
@@ -168,9 +168,8 @@ that has:
 
 A [=linear easing function=] has the following syntax:
 
-<dfn function lt="linear()">linear(<<linear-stop-list>>)</dfn>
-
 <pre class="prod">
+  <dfn>&lt;linear-easing-function></dfn> = <dfn function lt="linear()">linear(<<linear-stop-list>>)</dfn>
   <dfn>&lt;linear-stop-list></dfn> = [ <<linear-stop>> ]#
   <dfn>&lt;linear-stop></dfn> = <<number>> && <<linear-stop-length>>?
   <dfn>&lt;linear-stop-length></dfn> = <<percentage>>{1,2}