ALSA: usb-audio: scarlett2: Fix 18i8 Gen 2 PCM Input count

The 18i8 Gen 2 has 8 PCM Inputs, not 20. Fix the ports entry in
s18i8_gen2_info.
Signed-off-by: Geoffrey D. Bennett <g@b4.vu>
Link: https://lore.kernel.org/r/20210620164625.GA9165@m.b4.vuSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/usb/mixer_scarlett_gen2.c

@@ -358,7 +358,7 @@ static const struct scarlett2_device_info s18i8_gen2_info = {
 		},
 		[SCARLETT2_PORT_TYPE_PCM] = {
 			.id = 0x600,
-			.num = { 20, 18, 18, 14, 10 },
+			.num = { 8, 18, 18, 14, 10 },
 			.src_descr = "PCM %d",
 			.src_num_offset = 1,
 			.dst_descr = "PCM %02d Capture"