Truly check for `! empty()` instead of falsey `''` when determining whether to add `LIMIT` clause to SQL in `wp_get_archives()`.

Props jjeaton for the initial patch.
Fixes #27834.

Built from https://develop.svn.wordpress.org/trunk@28560


git-svn-id: http://core.svn.wordpress.org/trunk@28386 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/general-template.php

@@ -1192,7 +1192,7 @@ function wp_get_archives( $args = '' ) {
 		$r['type'] = 'monthly';
 	}
 
-	if ( '' != $r['limit'] ) {
+	if ( ! empty( $r['limit'] ) ) {
 		$r['limit'] = absint( $r['limit'] );
 		$r['limit'] = ' LIMIT ' . $r['limit'];
 	}