Bug 37759: Duplicated "Set library" menu item caused by bad merge

Bug 37759: Duplicated "Set library" menu item caused by bad merge

This patch removes an unnecessary block of markup accidentally left
behind during a rebase of Bug 35402, removing a duplicate "Set
library..." menu item from the header menu in the staff interface.

After the batch, users who have permission to change their logged-in
library should see only a single "Set library..." menu item in the user
menu found on the right-hand side of the header menu.

Signed-off-by: Roman Dolny <roman.dolny@jezuici.pl>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>