atmel, at91: fix smartweb board

since commit: f8b7fff1d5c5 "serial: atmel_usart: Add clk support"

smartweb board comes not up anymore. Fix it.

Signed-off-by: Heiko Schocher <hs@denx.de>
Acked-by: Wenyou Yang <wenyou.yang@microchip.com>
4 files changed