rpmsg: Update rpmsg_chrdev_register_device function

The rpmsg_chrdev driver has been replaced by the rpmsg_ctrl driver
for the /dev/rpmsg_ctrlX devices management. The reference for the
driver override is now the rpmsg_ctrl.

Update the rpmsg_chrdev_register_device function to reflect the update,
and rename the function to use the rpmsg_ctrldev prefix.

The platform drivers are updated accordingly.

Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@foss.st.com>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20220124102524.295783-8-arnaud.pouliquen@foss.st.com

drivers/rpmsg/rpmsg_ctrl.c

@@ -179,7 +179,7 @@ static struct rpmsg_driver rpmsg_ctrldev_driver = {
 	.probe = rpmsg_ctrldev_probe,
 	.remove = rpmsg_ctrldev_remove,
 	.drv = {
-		.name = "rpmsg_chrdev",
+		.name = "rpmsg_ctrl",
 	},
 };