ALSA: indigo-express: add missing 64KHz flags

Indigo-express cards also support 64KHz sampling rate: this patch adds
missing SNDRV_PCM_RATE_64000 flags.

Signed-off-by: Giuliano Pochini <pochini@shiny.it>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/echoaudio/indigoiox.c b/sound/pci/echoaudio/indigoiox.c
index aebee27..eb3819f 100644
--- a/sound/pci/echoaudio/indigoiox.c
+++ b/sound/pci/echoaudio/indigoiox.c
@@ -89,6 +89,7 @@
 	.rates = 	SNDRV_PCM_RATE_32000 |
 			SNDRV_PCM_RATE_44100 |
 			SNDRV_PCM_RATE_48000 |
+			SNDRV_PCM_RATE_64000 |
 			SNDRV_PCM_RATE_88200 |
 			SNDRV_PCM_RATE_96000,
 	.rate_min = 32000,