usb: io_ti: Make edge_remove_sysfs_attrs the port_remove method.

Calling edge_remove_sysfs_attrs from edge_disconnect is too late
as the device has already been removed from sysfs.

Do the simple and obvious thing and make edge_remove_sysfs_attrs
the port_remove method.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Reported-by: Wolfgang Frisch <wfpub@roembden.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>