ALSA: hdspm - Fix default value in SNDRV_HDSPM_IOCTL_GET_LTC

Use enum hdspm_ltc_format's fps_30 (corresponds to 4) instead of 30,
Other case branches return 1, 2 or 3 respectively, so 30 obviously is
wrong.

Since SNDRV_HDSPM_IOCTL_GET_LTC had never been working due to a
copy&paste error in hdspm.h, this change doesn't break userspace.
Signed-off-by: Adrian Knoth <adi@drcomp.erfurt.thur.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/rme9652/hdspm.c

@@ -6311,7 +6311,7 @@ static int snd_hdspm_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
 				ltc.format = fps_2997;
 				break;
 			default:
-				ltc.format = 30;
+				ltc.format = fps_30;
 				break;
 			}
 			if (i & HDSPM_TCO1_set_drop_frame_flag) {