parisc: Add support for SuperIO chip

Allow PDC to detect the NS SuperIO chip as built-in on various C-class
machines, like C3700. In SeaBIOS we want to allow booting from the IDE
chip, and output to the serial ports.

Signed-off-by: Abizer Lokhandwala <abizerlokhandwalastd10@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>