ASoC: rockchip: i2s: Fix Kconfig for I2S device driver

Currently, CONFIG_SND_SOC_ROCKCHIP_I2S could also be selected
without having CONFIG_SND_SOC_ROCKCHIP enabled.

As this makes no sense, a Kconfig dependency is added to
CONFIG_SND_SOC_ROCKCHIP_I2S. This will make the item visible only if
CONFIG_SND_SOC_ROCKCHIP is enabled.

Additionally, as the code connected to CONFIG_SND_SOC_ROCKCHIP_I2S
depends on CONFIG_SND_SOC_GENERIC_DMAENGINE_PCM, the dependency
is moved to reflect this more clearly.
Signed-off-by: Andreas Ruprecht <rupran@einserver.de>
Reported-by: Jim Davis <jim.epost@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/rockchip/Kconfig

 config SND_SOC_ROCKCHIP
 	tristate "ASoC support for Rockchip"
 	depends on COMPILE_TEST || ARCH_ROCKCHIP
-	select SND_SOC_GENERIC_DMAENGINE_PCM
 	help
 	  Say Y or M if you want to add support for codecs attached to
 	  the Rockchip SoCs' Audio interfaces. You will also need to
@@ -9,7 +8,8 @@ config SND_SOC_ROCKCHIP
 
 config SND_SOC_ROCKCHIP_I2S
 	tristate "Rockchip I2S Device Driver"
-	depends on CLKDEV_LOOKUP
+	depends on CLKDEV_LOOKUP && SND_SOC_ROCKCHIP
+	select SND_SOC_GENERIC_DMAENGINE_PCM
 	help
 	  Say Y or M if you want to add support for I2S driver for
 	  Rockchip I2S device. The device supports upto maximum of