[MPlayer-dev-eng] check for XFree86-VidModeExtension broken for xfree 3.3.x

[Diego Biurrun]

Trent Piepho writes:
> The XFree86-VidModeExtension extension isn't detected, when it used to be
> in older versions of mplayer.  This is problematic, as xfree 3.3.x doesn't
> have DGA2 to switch modes.  This patch fixes it.
> 
> +  _xf86xk=no

You add a check so you should also add --disable and --enable options
to configure.

Diego