tty: Change the order of collection

There are two object for TTY files -- the file itself and tty_info.
The latter is effectively an inode image. Right now we collect infos
before files, so that latter can find former and attach to it.

In order to move tty files on generic file entry we need to collect
files very early, much earlier, that infos. So here's the patch that
changes the order of tty file vs info collection.

The general idea is -- when collecting files put them in a list and
when an info arrives it walks that list and attaches ttys to self.
Next patches will also add some optimization available with that
scheme.

Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>