[css-grid-2] Fix links.

Author: fantasai

css-grid-2/Overview.bs

@@ -3622,9 +3622,9 @@ Subgrids</h2>
 					.inner = [center info-start] [info-end photos-start] [main-end photos-end]
 				</pre>
 
-				Notice that all the [=explicitly-assigned names=]
+				Notice that all the [=explicitly-assigned line names=]
 				inherit straight through to .inner,
-				but the [=implicitly-assigned names=] are calculated based on
+				but the [=implicitly-assigned line names=] are calculated based on
 				each [=subgrid=]'s overlap of the original <a>named grid area</a>.
 			</div>