[PARISC] defconfig updates

Make the defconfig more generally useful. Turn on IPv6, modules,
cardbus, etc. Boots 32bit on 715 with HIL, B160L with sound,
PrecisionBook, and C3000.
Signed-off-by: Helge Deller <deller@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>