ASoC: rsnd: SND_SOC_RCAR doesn't depend on DMA_OF

ASoC: rsnd: SND_SOC_RCAR doesn't depend on DMA_OF

8616774("ASoC: rnsd: fix build regression without CONFIG_OF")
added "depends on DMA_OF" in SND_SOC_RCAR to avoid compile error of

    sound/built-in.o: In function `rsnd_dma_request_channel':
    :(.text+0x9fb84): undefined reference to `of_dma_request_slave_channel'

But, it was OF base DMAEngine API definition issue, not SND_SOC_RCAR
issue. This patch remove DMA_OF dependence.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>