powerpc/83xx: add kmcoge5ne board support

powerpc/83xx: add kmcoge5ne board support

This board is a MPC8360 board. Two flashes are present
a NOR flash were u-boot and the u-boot environment is stored
and a NAND flash for the application code. This board has 512MB
SDRAM.

Additionaly we introduce a common km8360.h file and convert kmeter1 to
use this.

Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Christian Herzig <christian.herzig@keymile.com>
cc: Kim Phillips <kim.phillips@freescale.com>
cc: Valentin Longchamp <valentin.longchamp@keymile.com>
cc: Gerlando Falauto <gerlando.falauto@keymile.com>
cc: Heiko Schocher <hs@denx.de>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>