platform/x86/intel/sdsi: Poll on ready bit for writes

Due to change in firmware flow, update mailbox writes to poll on ready bit
instead of run_busy bit. This change makes the polling method consistent
for both writes and reads, which also uses the ready bit.

Fixes: 2546c60 ("platform/x86: Add Intel Software Defined Silicon driver")
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Link: https://lore.kernel.org/r/20220420155622.1763633-3-david.e.box@linux.intel.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>

Author: debox1

drivers/platform/x86/intel/sdsi.c

@@ -245,8 +245,8 @@ static int sdsi_mbox_cmd_write(struct sdsi_priv *priv, struct sdsi_mbox_info *in
 		  FIELD_PREP(CTRL_PACKET_SIZE, info->size);
 	writeq(control, priv->control_addr);
 
-	/* Poll on run_busy bit */
-	ret = readq_poll_timeout(priv->control_addr, control, !(control & CTRL_RUN_BUSY),
+	/* Poll on ready bit */
+	ret = readq_poll_timeout(priv->control_addr, control, control & CTRL_READY,
 				 MBOX_POLLING_PERIOD_US, MBOX_TIMEOUT_US);
 
 	if (ret)