luci-base: luci.js: don't abort finished xhr objects

Calling abort() on a finished xhr object will clear properties such
as status which can confuse code relying on legacy LuCI request
helper functions.

Signed-off-by: Jo-Philipp Wich <jo@mein.io>

modules/luci-base/htdocs/luci-static/resources/luci.js

@@ -393,11 +393,6 @@
 					.then(resolveFn.bind(this, response))
 					.catch(rejectFn.bind(this));
 			}
-
-			try {
-				xhr.abort();
-			}
-			catch(e) {}
 		},
 
 		get: function(url, options) {