ALSA: ctxfi - Fix supported PCM formats

The device seems supporting only U8, S16, S24_3LE, S32.  Other linear
formats result in bad outputs.

Also, added the support for 32bit float format, which wasn't listed
in the original code.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/ctxfi/ctatc.c b/sound/pci/ctxfi/ctatc.c
index 675dd4c..268ecc4 100644
--- a/sound/pci/ctxfi/ctatc.c
+++ b/sound/pci/ctxfi/ctatc.c
@@ -170,16 +170,15 @@
 {
 	switch (snd_format) {
 	case SNDRV_PCM_FORMAT_U8:
-	case SNDRV_PCM_FORMAT_S8:
 		return SRC_SF_U8;
 	case SNDRV_PCM_FORMAT_S16_LE:
-	case SNDRV_PCM_FORMAT_U16_LE:
 		return SRC_SF_S16;
 	case SNDRV_PCM_FORMAT_S24_3LE:
 		return SRC_SF_S24;
-	case SNDRV_PCM_FORMAT_S24_LE:
 	case SNDRV_PCM_FORMAT_S32_LE:
 		return SRC_SF_S32;
+	case SNDRV_PCM_FORMAT_FLOAT_LE:
+		return SRC_SF_F32;
 	default:
 		printk(KERN_ERR "ctxfi: not recognized snd format is %d \n",
 			snd_format);