mailbox: zynqmp-ipi: Remove redundant mbox_controller_unregister() call

[ Upstream commit 341867f ]

The controller is registered using the device-managed function
'devm_mbox_controller_register()'. As documented in mailbox.c, this
ensures the devres framework automatically calls
mbox_controller_unregister() when device_unregister() is invoked, making
the explicit call unnecessary.

Remove redundant mbox_controller_unregister() call as
device_unregister() handles controller cleanup.

Fixes: 4981b82 ("mailbox: ZynqMP IPI mailbox controller")
Signed-off-by: Harini T <harini.t@amd.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: Harini T

drivers/mailbox/zynqmp-ipi-mailbox.c

@@ -894,7 +894,6 @@ static void zynqmp_ipi_free_mboxes(struct zynqmp_ipi_pdata *pdata)
 	for (; i >= 0; i--) {
 		ipi_mbox = &pdata->ipi_mboxes[i];
 		if (ipi_mbox->dev.parent) {
-			mbox_controller_unregister(&ipi_mbox->mbox);
 			if (device_is_registered(&ipi_mbox->dev))
 				device_unregister(&ipi_mbox->dev);
 		}