MDL-27084: mod/feedback fix bad syntax in database query

mod/feedback/lib.php

@@ -1786,10 +1786,10 @@ function feedback_get_page_to_continue($feedbackid, $courseid = false, $guestid
 
     $params = array();
     if($courseid) {
-        $courseselect = "fv.course_id = :courseid";
+        $courseselect = "AND fv.course_id = :courseid";
         $params['courseid'] = $courseid;
     }else {
-        $courseselect = "1";
+        $courseselect = '';
     }
 
     if($guestid) {
@@ -1807,7 +1807,7 @@ function feedback_get_page_to_continue($feedbackid, $courseid = false, $guestid
               WHERE fc.id = fv.completed
                     $userselect
                     AND fc.feedback = :feedbackid
-                    AND $courseselect
+                    $courseselect
                     AND fi.id = fv.item
          $usergroup";
     $params['feedbackid'] = $feedbackid;
@@ -2779,4 +2779,4 @@ function feedback_init_feedback_session() {
             $SESSION->feedback = new stdClass();
         }
     }
-}
+}