Undo 3d5d3709; have fixed installer to just use 64 bit reg view

see

https://gitlab.developers.cam.ac.uk/ch/co/wpkg/pstools-nsis/-/commit/9bb33f21d7714adecc066978ec6488cd1475b9b7

for the fix to the nsis installer

packages/pstools.xml

@@ -4,12 +4,8 @@
     <variable name="version" value="2.45.1" />
 
     <!-- N.B. the installer takes care of creating and removing this reg key as needed -->
-    <!-- I've not figured out why NSIS sometimes puts the key in wow6432node though so
-         we'll accept either reg key existing -->
-    <check type="logical" condition="or">
-      <check type='registry' condition='equals' path='HKLM\software\ucam_wpkg.cam.ac.uk\pstools\version' value="%version%"/>
-      <check type='registry' condition='equals' path='HKLM\software\wow6432node\ucam_wpkg.cam.ac.uk\pstools\version' value="%version%"/>
-    </check>
+    <check type='registry' condition='equals' path='HKLM\software\ucam_wpkg.cam.ac.uk\pstools\version' value="%version%"/>
+
     <!-- the exe is built by https://gitlab.developers.cam.ac.uk/ch/co/wpkg/pstools-nsis; see README contained therein -->
 
     <install cmd='%wpkgsoftware%\microsoft.com\pstools\pstools-%version%.exe' />