powerpc: 83xx: add support for the kmeter1 board

This patch adds support for the kmeter1 board from Keymile,
based on a Freescale MPC8360 CPU.

- serial console on UART 1
- 256 MB DDR2 RAM
- 64 MB NOR Flash
- Ethernet RMII Mode over UCC4
- PHY SMSC LAN8700

Signed-off-by: Heiko Schocher <hs@denx.de>