[css2] Minor vocab change

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extra : convert_revision : svn%3A73dc7c4b-06e6-40f3-b4f7-9ed1dbc14bfc/trunk%401044

Author: ianbjacobs

css2/visufx.src

@@ -185,7 +185,7 @@ of the containing block of boxes generated for the element.
 name="value-def-shape"
 class="value-def"><strong>&lt;shape&gt;</strong></a></span>
 
-<dd>In CSS2, the only legal &lt;shape&gt; value is:
+<dd>In CSS2, the only valid &lt;shape&gt; value is:
 rect (<span
 class="value-inst-top">&lt;top&gt;</span> <span
 class="value-inst-right">&lt;right&gt;</span> <span