ASoC: samsung: Use CONFIG_ARCH_S3C64XX to check for S3C64XX support

Since CONFIG_PLAT_S3C64XX is going to be removed, this patch modifies
the s3c-i2s-v2 driver to use the proper way of checking for S3C64xx
support - CONFIG_ARCH_S3C64XX.
Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Acked-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

sound/soc/samsung/s3c-i2s-v2.c

@@ -31,11 +31,7 @@
 #undef S3C_IIS_V2_SUPPORTED
 
 #if defined(CONFIG_CPU_S3C2412) || defined(CONFIG_CPU_S3C2413) \
-	|| defined(CONFIG_CPU_S5PV210)
-#define S3C_IIS_V2_SUPPORTED
-#endif
-
-#ifdef CONFIG_PLAT_S3C64XX
+	|| defined(CONFIG_ARCH_S3C64XX) || defined(CONFIG_CPU_S5PV210)
 #define S3C_IIS_V2_SUPPORTED
 #endif