ppc, arm: adapt keymile header

- adapt copyright string
- change bootdelay to 2 seconds
- set max number of command args to 32
- set I/O buffer size to 512

Signed-off-by: Holger Brunck <holger.brunck@keymile.com>
Signed-off-by: Heiko Schocher <hs@denx.de>
Acked-by: Kim Phillips <kim.phillips@freescale.com>
cc: Kim Phillips <kim.phillips@freescale.com>
cc: Wolfgang Denk <wd@denx.de>
cc: Valentin Longchamp <valentin.longchamp@keymile.com>