Move instruction where it is relevant

People need to be instructed to empty the trash when cleaning available
disk space, not in the "Empty the trash" section.

wiki/src/doc/encryption_and_privacy/secure_deletion.mdwn

@@ -87,9 +87,6 @@ you to recover your work in case LibreOffice stops responding).</p>
 Emptying the trash
 ==================
 
-Before considering [[securely cleaning the available space on a
-disk|secure_deletion#clean_disk_space]], make sure to empty the trash.
-
   1. Open the <span class="application">Files</span> browser.
 
   1. Click on the disk on which you want to empty the trash in the left
@@ -133,6 +130,8 @@ be deleted during the operation.
   1. Click on the disk that you want to clean in the left pane to
      navigate to the root of this disk.
 
+  1. [[Empty the trash.|secure_deletion#empty_trash]]
+
   1. Right-click in empty space in the right pane and choose <span
      class="guimenuitem">Wipe available diskspace</span>.