intel TVOut default margins

[Robert Lowery]

The default margins in i830_tv.c give me a lot of black borders,
particularly at the bottom of the screen.  Is there any reason these
values in particular were chosen as defaults?

    /* BIOS margin values */
    dev_priv->margin[TV_MARGIN_LEFT] = 54;
    dev_priv->margin[TV_MARGIN_TOP] = 36;
    dev_priv->margin[TV_MARGIN_RIGHT] = 46;
    dev_priv->margin[TV_MARGIN_BOTTOM] = 37;

I know xrandr can change them, the above values just seem a little strange
to have as defaults.