check_swap: Fix the plugin name that appears in the comment

Signed-off-by: Davide Madrisan <davide.madrisan@gmail.com>

plugins/check_swap.c

@@ -8,7 +8,7 @@
 * 
 * Description:
 * 
-* This file contains the check_disk plugin
+* This file contains the check_swap plugin
 * 
 * 
 * This program is free software: you can redistribute it and/or modify