[css-images-3][editorial] Fix markup

Author: tabatkins

css-images-3/Overview.bs

@@ -1607,7 +1607,7 @@ Image Processing {#image-processing}
 
 			Note: [[#url-metadata]] imposes some restrictions on what metadata can be used.
 
-		<dt><dfn lt="<angle>|flip|<angle> || flip"><<angle>> || flip</dfn>
+		<dt><dfn lt="<angle>|flip"><<angle>> || flip</dfn>
 		<dd>
 			Positive <<angle>> values cause the image to be rotated to the right
 			(in a clockwise direction),