MAINTAINERS: orphan SIS FRAMEBUFFER DRIVER

This was triggered by the fact that the webpage:

  http://www.winischhofer.net/linuxsisvga.shtml



cannot be reached anymore.

Thomas Winischhofer is still reachable at the given email address, but he
has not been active since 2005.

Mark the SIS FRAMEBUFFER DRIVER as orphan to reflect the current state.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Helge Deller <deller@gmx.de>