[Fedora-packaging] Fix Packaging:ScriptletSnippets#Icon_Cache

[Michael Schwendt]

https://fedoraproject.org/wiki/Packaging:ScriptletSnippets#Icon_Cache

>  %post
>  /bin/touch --no-create %{_datadir}/icons/hicolor &>/dev/null || :
>  
>  %postun
>  if [ $1 -eq 0 ] ; then
>      /bin/touch --no-create %{_datadir}/icons/hicolor &>/dev/null
>      /usr/bin/gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || :
>  fi
>  
>  %posttrans
>  /usr/bin/gtk-update-icon-cache %{_datadir}/icons/hicolor &>/dev/null || : 
Somebody with write-access to that page, please add the missing " || :" to
the end of the /bin/touch line in the %postun scriptlet.

Then the code would be consistent with its explanation on the page.