powerpc/8xx: Add support for the MPC8xx based boards from TQC

Supported SMC1 (serial console), SCC1 Ethernet (10Mbps HD).
FEC Ethernet, 8MB NOR CFI Flash.

Tested on STK8xx with TQM860L (with FEC) and with TQM855M (without FEC).

Signed-off-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>