af_redditimgur: make sure content_link is defined even if content dupcheck is disabled

plugins/af_redditimgur/init.php

@@ -301,9 +301,10 @@ class Af_RedditImgur extends Plugin {
 			@$doc->loadHTML($article["content"]);
 			$xpath = new DOMXPath($doc);
 
-			if ($this->host->get($this, "enable_content_dupcheck")) {
 			$content_link = $xpath->query("(//a[contains(., '[link]')])")->item(0);
 
+			if ($this->host->get($this, "enable_content_dupcheck")) {
+
 				if ($content_link) {
 					$content_href = db_escape_string($content_link->getAttribute("href"));
 					$entry_guid = db_escape_string($article["guid_hashed"]);