ASoC: atmel_wm8904: constify snd_soc_ops structures

Check for snd_soc_ops structures that are only stored in the ops field of a
snd_soc_dai_link structure.  This field is declared const, so snd_soc_ops
structures that have this property can be declared as const also.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct snd_soc_ops i@p = { ... };

@ok1@
identifier r.i;
struct snd_soc_dai_link e;
position p;
@@
e.ops = &i@p;

@ok2@
identifier r.i, e;
position p;
@@
struct snd_soc_dai_link e[] = { ..., { .ops = &i@p, }, ..., };

@bad@
position p != {r.p,ok1.p,ok2.p};
identifier r.i;
struct snd_soc_ops e;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
 struct snd_soc_ops i = { ... };
// </smpl>

The effect on the layout of the .o file is shown by the following output of
the size command, first before then after the transformation:

   text    data     bss     dec     hex filename
   2611    1536       0    4147    1033 sound/soc/atmel/atmel_wm8904.o
   2675    1480       0    4155    103b sound/soc/atmel/atmel_wm8904.o

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>