Patch for 8xx watchdog handler for >=2.6.10

Hi,

our mpc 823 based embedded board (STB, dbox2) would hang with every 
kernel starting from 2.6.10-rc1_linuxppc. I tracked the problem down to 
the watchdog interrupt handler setup and the new generic interrupt 
handling routines (which caused an uninitialized pointer because kmalloc 
was used before the kmem_cache was initialized).

As said, this was only an issue if CONFIG_8xx_WDT was set.

I have attached a simple patch for the handler.

Regards,
Carsten Juttner