ASoC: SOF: Do not send cmd via SHIM register

We use shim registers only to notify the other
side that a message was sent. The actual information
for the message is transmitted via mailbox.

cmd information inside shim register is not used by
the DSP, so we remove it to avoid confusion.

Signed-off-by: Daniel Baluta <daniel.baluta@gmail.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/byt.c

@@ -373,13 +373,10 @@ static irqreturn_t byt_irq_thread(int irq, void *context)
 
 static int byt_send_msg(struct snd_sof_dev *sdev, struct snd_sof_ipc_msg *msg)
 {
-	u64 cmd = msg->header;
-
 	/* send the message */
 	sof_mailbox_write(sdev, sdev->host_box.offset, msg->msg_data,
 			  msg->msg_size);
-	snd_sof_dsp_write64(sdev, BYT_DSP_BAR, SHIM_IPCX,
-			    cmd | SHIM_BYT_IPCX_BUSY);
+	snd_sof_dsp_write64(sdev, BYT_DSP_BAR, SHIM_IPCX, SHIM_BYT_IPCX_BUSY);
 
 	return 0;
 }