ASoC: imx: let SND_MXC_SOC_FIQ select FIQ

CONFIG_FIQ is only needed when CONFIG_SND_MXC_SOC_FIQ is selected to
build imx-pcm-fiq.c, so let SND_MXC_SOC_FIQ select FIQ.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/imx/Kconfig

 menuconfig SND_IMX_SOC
 	tristate "SoC Audio for Freescale i.MX CPUs"
 	depends on ARCH_MXC
-	select FIQ
 	select SND_SOC_AC97_BUS
 	help
 	  Say Y or M if you want to add support for codecs attached to
@@ -11,6 +10,7 @@ menuconfig SND_IMX_SOC
 if SND_IMX_SOC
 
 config SND_MXC_SOC_FIQ
+	select FIQ
 	tristate
 
 config SND_MXC_SOC_MX2