ppc32: Adds support for the LITE5200B dev board

This LITE5200B devboard is the new development board for the
Freescale MPC5200 processor. It has two PCI slots and so a
different PCI IRQ routing.
Signed-off-by: NJohn Rigby <jrigby@freescale.com>
Signed-off-by: NSylvain Munaut <tnt@246tNt.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>