ASoC: Intel: atom: make sst_platform_compr_ops const

Make this const as it not modified in the file referencing it.
It only stored in the const field 'compr_ops' of a snd_soc_platform_driver
structure. Also, add const to the declaration in the header file.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/atom/sst-mfld-platform-compress.c

@@ -259,7 +259,7 @@ static int sst_platform_compr_set_metadata(struct snd_compr_stream *cstream,
 	return stream->compr_ops->set_metadata(sst->dev, stream->id, metadata);
 }
 
-struct snd_compr_ops sst_platform_compr_ops = {
+const struct snd_compr_ops sst_platform_compr_ops = {
 
 	.open = sst_platform_compr_open,
 	.free = sst_platform_compr_free,

sound/soc/intel/atom/sst-mfld-platform.h

@@ -25,7 +25,7 @@
 #include "sst-atom-controls.h"
 
 extern struct sst_device *sst;
-extern struct snd_compr_ops sst_platform_compr_ops;
+extern const struct snd_compr_ops sst_platform_compr_ops;
 
 #define SST_MONO		1
 #define SST_STEREO		2