ASoC: codecs: add const to snd_soc_codec_driver structures

Declare snd_soc_codec_driver structures as const as they are only passed
as an argument to the function snd_soc_register_codec. This argument is
of type const, so declare the structures with this property as const.
In file codecs/sn95031.c, snd_soc_codec_driver structure is also used in
a copy operation along with getting passed to snd_soc_register_codec.
So, it can be made const too.
Done using Coccinelle:

@match disable optional_qualifier@
identifier s;
position p;
@@
static struct snd_soc_codec_driver s@p={...};

@good1@
identifier match.s;
position p;
@@
snd_soc_register_codec(...,&s@p,...)

@bad@
identifier match.s;
position p!={match.p,good1.p};
@@
s@p

@depends on !bad disable optional_qualifier@
identifier match.s;
@@
static
+const
struct snd_soc_codec_driver s={...};

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/pcm1681.c

@@ -288,7 +288,7 @@ static const struct regmap_config pcm1681_regmap = {
 	.readable_reg		= pcm1681_accessible_reg,
 };
 
-static struct snd_soc_codec_driver soc_codec_dev_pcm1681 = {
+static const struct snd_soc_codec_driver soc_codec_dev_pcm1681 = {
 	.component_driver = {
 		.controls		= pcm1681_controls,
 		.num_controls		= ARRAY_SIZE(pcm1681_controls),