ASoC: MPC5200: Eliminate duplicate include of of_device.h

Eliminate duplicate  #include <linux/of_device.h>  from
sound/soc/fsl/mpc5200_dma.c

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>