greybus: gb-audio: cpu_dai.fmt does not exist in v4.1

The asoc_simple_dai structure does not contain the 'fmt'
member in Linux kernel version v4.1 and later so only
build code that uses it when the kernel version is earlier
than v4.1.
Signed-off-by: Mark A. Greer <mgreer@animalcreek.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/audio.c

@@ -118,7 +118,9 @@ static struct asoc_simple_card_info *setup_card_info(int device_count)
 	sprintf(obj->codec_name, "rt5645.%d-%04x", RT5647_I2C_ADAPTER_NR,
 		RT5647_I2C_ADDR);
 	obj->card_info.codec_dai.name	= "rt5645-aif1";
+#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 1, 0)
 	obj->card_info.codec_dai.fmt	= SND_SOC_DAIFMT_CBS_CFS;
+#endif
 	obj->card_info.codec_dai.sysclk	= 12288000;
 #else
 	sprintf(obj->codec_name, "spdif-dit");