regression, blocker for 1.8.5rc1

viewing history of a text item :

Undefined variable: itm[/srv/www/htdocs/zabbix/history.php:313]

that seems to be a typo - itm -> item

this specific case was introduced in trunk in rev 17524, but it's also present in 1.8.

also note that ./include/forms.inc.php has multiple "itm" & "itmid" refs - if those are not typos, it is a terrible, terrible variable name and should be changed anyway