ASoC: cs42l51: Constify struct i2c_device_id

ASoC: cs42l51: Constify struct i2c_device_id

'struct i2c_device_id' is not modified in this driver.

Constifying this structure moves some data to a read-only section, so
increase overall security.

While at it, also add some space to be consistent with cs42l51_of_match a
few lines below.

On a x86_64, with allmodconfig:
Before:
======
   text	   data	    bss	    dec	    hex	filename
   1551	    384	     16	   1951	    79f	sound/soc/codecs/cs42l51-i2c.o

After:
=====
   text	   data	    bss	    dec	    hex	filename
   1631	    304	     16	   1951	    79f	sound/soc/codecs/cs42l51-i2c.o

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://patch.msgid.link/d5e686f47eddb14245d0fde693ff77ae749f7a08.1731689646.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Mark Brown <broonie@kernel.org>