atl1: fix bad ioread address

An ioread32 statement reads the wrong address.  Fix it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jay Cliburn <jacliburn@bellsouth.net>
Signed-off-by: Chris Snook <csnook@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>