ASoC: kirkwood: Enable build on non-Kirkwood platforms

Improve build coverage by enabling build on other platforms if COMPILE_TEST
is enabled.
Signed-off-by: Mark Brown <broonie@linaro.org>

sound/soc/kirkwood/Kconfig

 config SND_KIRKWOOD_SOC
 	tristate "SoC Audio for the Marvell Kirkwood chip"
-	depends on ARCH_KIRKWOOD
+	depends on ARCH_KIRKWOOD || COMPILE_TEST
 	help
 	  Say Y or M if you want to add support for codecs attached to
 	  the Kirkwood I2S interface. You will also need to select the
@@ -11,7 +11,7 @@ config SND_KIRKWOOD_SOC_I2S
 
 config SND_KIRKWOOD_SOC_OPENRD
 	tristate "SoC Audio support for Kirkwood Openrd Client"
-	depends on SND_KIRKWOOD_SOC && (MACH_OPENRD_CLIENT || MACH_OPENRD_ULTIMATE)
+	depends on SND_KIRKWOOD_SOC && (MACH_OPENRD_CLIENT || MACH_OPENRD_ULTIMATE || COMPILE_TEST)
 	depends on I2C
 	select SND_KIRKWOOD_SOC_I2S
 	select SND_SOC_CS42L51
@@ -21,7 +21,7 @@ config SND_KIRKWOOD_SOC_OPENRD
 
 config SND_KIRKWOOD_SOC_T5325
 	tristate "SoC Audio support for HP t5325"
-	depends on SND_KIRKWOOD_SOC && MACH_T5325 && I2C
+	depends on SND_KIRKWOOD_SOC && (MACH_T5325 || COMPILE_TEST) && I2C
 	select SND_KIRKWOOD_SOC_I2S
 	select SND_SOC_ALC5623
 	help