soc: ti: wkup_m3_ipc: Send NULL dummy message instead of pointer message

mbox_send_message() sends a u32 bit message, not a pointer to a message.
We only convert to a pointer type as a generic type. If we want to send
a dummy message of 0, then simply send 0 (NULL).

Signed-off-by: Andrew Davis <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Nishanth Menon <[e-mail]>

drivers/soc/ti/wkup_m3_ipc.c

···
 #include <linux/irq.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/omap-mailbox.h>
 #include <linux/platform_device.h>
 #include <linux/remoteproc.h>
 #include <linux/suspend.h>
···
 static int wkup_m3_ping(struct wkup_m3_ipc *m3_ipc)
 {
 	struct device *dev = m3_ipc->dev;
-	mbox_msg_t dummy_msg = 0;
 	int ret;
 
 	if (!m3_ipc->mbox) {
···
 	 * the RX callback to avoid multiple interrupts being received
 	 * by the CM3.
 	 */
-	ret = mbox_send_message(m3_ipc->mbox, &dummy_msg);
+	ret = mbox_send_message(m3_ipc->mbox, NULL);
 	if (ret < 0) {
 		dev_err(dev, "%s: mbox_send_message() failed: %d\n",
 			__func__, ret);
···
 static int wkup_m3_ping_noirq(struct wkup_m3_ipc *m3_ipc)
 {
 	struct device *dev = m3_ipc->dev;
-	mbox_msg_t dummy_msg = 0;
 	int ret;
 
 	if (!m3_ipc->mbox) {
···
 		return -EIO;
 	}
 
-	ret = mbox_send_message(m3_ipc->mbox, &dummy_msg);
+	ret = mbox_send_message(m3_ipc->mbox, NULL);
 	if (ret < 0) {
 		dev_err(dev, "%s: mbox_send_message() failed: %d\n",
 			__func__, ret);