Bug 13418: Clean C4::VirtualShelves::Page - Part 2

Bug 13418: Clean C4::VirtualShelves::Page - Part 2

I don't understand at all the usefulness of $privshelflist and
$privtotshelves in C4::VirtualShelves::Page
They look useless.

If you deep in the git history, you will find
    commit 25eb36f21fe952118327d2c84dfef5d38eee31a7
    Bug #2531 Cannot delete private shelf

I am not able to reproduce this issue after this patch

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>