ramips: mt7620: ralink-i2s: fix modpost error

Fixes the following error when building without CONFIG_MODULE_STRIPPED:
  FATAL: modpost: sound/soc/ralink/snd-soc-ralink-i2s: struct
  of_device_id is not terminated with a NULL entry!

Signed-off-by: Ilya Lipnitskiy <[email protected]>

target/linux/ramips/patches-5.10/835-asoc-add-mt7620-support.patch

@@ -78,7 +78,7 @@ Signed-off-by: John Crispin <[email protected]>
 +obj-$(CONFIG_SND_RALINK_SOC_I2S) += snd-soc-ralink-i2s.o
 --- /dev/null
 +++ b/sound/soc/ralink/ralink-i2s.c
-@@ -0,0 +1,965 @@
+@@ -0,0 +1,966 @@
 +/*
 + *  Copyright (C) 2010, Lars-Peter Clausen <[email protected]>
 + *  Copyright (C) 2016 Michael Lee <[email protected]>
@@ -881,6 +881,7 @@ Signed-off-by: John Crispin <[email protected]>
 +		.data = (void *)&mt7621_i2s_data },
 +	{ .compatible = "mediatek,mt7628-i2s",
 +		.data = (void *)&mt7628_i2s_data },
++	{},
 +};
 +MODULE_DEVICE_TABLE(of, ralink_i2s_match_table);
 +