powerpc/476: add machine check handler for 47x core

The 47x core's MCSR varies from 44x, so it needs it's own machine check
handler.

Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
3 files changed