PPC405GPr support patch (and a small CPCI405 update)

Hi,

here is a small patch to support the new PPC405GPr (cputable.c).
Additionally I have included some updates for our CPCI405 board (rtc support
and default config update). This patch is against the current
linuxppc_2_4_devel tree.

By the way:
Upon looking into cputable.c I noticed that all NP4xx ppc's have the wrong
cache line size configured (total cache size in kB instead of cache line
size). May this cause some problems?

Ciao,
Stefan.