ASoC: Intel: Haswell: Remove set but not used variable 'stage_type'

Fixes gcc '-Wunused-but-set-variable' warning:

sound/soc/intel/haswell/sst-haswell-ipc.c: In function 'hsw_stream_message':
sound/soc/intel/haswell/sst-haswell-ipc.c:669:29: warning: variable 'stage_type' set but not used [-Wunused-but-set-variable]

It is never used since introduction in
commit ba57f682 ("ASoC: Intel: create haswell folder and move haswell platform files in")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/haswell/sst-haswell-ipc.c

@@ -345,11 +345,6 @@ static inline u32 msg_get_stream_type(u32 msg)
 	return (msg & IPC_STR_TYPE_MASK) >>  IPC_STR_TYPE_SHIFT;
 }
 
-static inline u32 msg_get_stage_type(u32 msg)
-{
-	return (msg & IPC_STG_TYPE_MASK) >>  IPC_STG_TYPE_SHIFT;
-}
-
 static inline u32 msg_get_stream_id(u32 msg)
 {
 	return (msg & IPC_STR_ID_MASK) >>  IPC_STR_ID_SHIFT;
@@ -666,13 +661,12 @@ static int hsw_module_message(struct sst_hsw *hsw, u32 header)
 
 static int hsw_stream_message(struct sst_hsw *hsw, u32 header)
 {
-	u32 stream_msg, stream_id, stage_type;
+	u32 stream_msg, stream_id;
 	struct sst_hsw_stream *stream;
 	int handled = 0;
 
 	stream_msg = msg_get_stream_type(header);
 	stream_id = msg_get_stream_id(header);
-	stage_type = msg_get_stage_type(header);
 
 	stream = get_stream_by_id(hsw, stream_id);
 	if (stream == NULL)