ASoC: rsnd: fixup rsnd_gen_dma_addr() for Gen1

ASoC: rsnd: fixup rsnd_gen_dma_addr() for Gen1

25f3d3a13feda9dae81b066bbbf22baccd96d0d7
(ASoC: rsnd: add rsnd_gen_dma_addr() for DMAC addr)
added rsnd_gen_dma_addr() to calculate DMA addr,
but, it is necessary only for Gen2.
This patch ignores Gen1 case.
Kernel will be panic without this patch.
Special thanks to Simon

Reported-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Mark Brown <broonie@linaro.org>