Remove sanitizeIdPName from system

We should allow more characters in the name of the IdP. As this is not a
value we use in the certificate itself, we need only clean out
html-values to stop XSS from happening.

Since we use htmlentities() for this, we can remove all references to
sanitizeIdPName() including the function itself. It is important to
remove this from admin.php as it could be difficult to add admins to
Subscribers with invalid names.

Reported-By: Thijs Kinkhorst <thijs@uvt.nl>
Signed-off-by: Henrik Austad <henrik@austad.us>
admin: do not combine truncate and escape for names with special chars

sub-admin pages must use the proper function for retrieving the name,
and in the legend, truncate should be used to avoid lengthy names to
mess with the layout.

When we have special characters, truncate and escape (functions of
smarty) do not play together nicely. The orgname is one value that we
sanitize well, so we can drop escape in the legend of these fields.

Signed-off-by: Henrik Austad <henrik@austad.us>