Fix memtest grub entry

The gparted image is named gparted-live-686 and no longer -486

grub/grub.cfg

@@ -146,7 +146,7 @@ menuentry "${lip_flavor} ${lip_version}${lip_extra_info} ${bits}bit (english, lo
 }
 
 menuentry "Tool: Memtest86+" {
-  loopback loop ($root)/gparted-live-i486.iso
+  loopback loop ($root)/gparted-live-i686.iso
   echo     "Loading memtest"
   linux16  (loop)/live/memtest
   echo 	   "Starting Memtest86Plus"