board: atmel: clean up the PMC_PLLICPR init code

Due to introducing the PMC_PLLICPR init function, use this
function to clean up the code.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Tested-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Andreas Bießmann <andreas.devel@googlemail.com>
4 files changed