ALSA: usb-audio: scarlett2: Remove incorrect S/PDIF comment

The 18i8 Gen 2 S/PDIF outputs are available at 192kHz, unlike
the 18i20 Gen 2. Remove the comment that says otherwise.
Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Link: https://lore.kernel.org/r/20210620164622.GA9155@m.b4.vuSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/mixer_scarlett_gen2.c

@@ -338,10 +338,6 @@ static const struct scarlett2_device_info s18i8_gen2_info = {
 		},
 		[SCARLETT2_PORT_TYPE_SPDIF] = {
 			.id = 0x180,
-			/* S/PDIF outputs aren't available at 192kHz
-			 * but are included in the USB mux I/O
-			 * assignment message anyway
-			 */
 			.num = { 2, 2, 2, 2, 2 },
 			.src_descr = "S/PDIF %d",
 			.src_num_offset = 1,