ALSA: line6: Remove struct usb_line6_podhd

It's identical with struct usb_line6.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/line6/podhd.c b/sound/usb/line6/podhd.c
index 5e4e02c..4ebe6ef 100644
--- a/sound/usb/line6/podhd.c
+++ b/sound/usb/line6/podhd.c
@@ -25,11 +25,6 @@
 	LINE6_PODHD500_1,
 };
 
-struct usb_line6_podhd {
-	/* Generic Line 6 USB data */
-	struct usb_line6 line6;
-};
-
 #define PODHD_BYTES_PER_FRAME 6	/* 24bit audio (stereo) */
 
 static struct snd_ratden podhd_ratden = {
@@ -176,7 +171,7 @@
 {
 	return line6_probe(interface, id,
 			   &podhd_properties_table[id->driver_info],
-			   podhd_init, sizeof(struct usb_line6_podhd));
+			   podhd_init, sizeof(struct usb_line6));
 }
 
 static struct usb_driver podhd_driver = {