staging: vc04_services: vchiq_core: Log through struct vchiq_instance

The handle_to_service() helper can return NULL, so `service` pointer
can indeed be set to NULL. So, do not log through service pointer
(which can cause NULL-deference), instead, use the vchiq_instance
function argument to get access to the struct device.

Fixes: f67af594 ("staging: vc04: Convert(and rename) vchiq_log_info() to use dynamic debug")
Reviewed-by: Ricardo B. Marliere <ricardo@marliere.net>
Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Link: https://lore.kernel.org/r/20231128201845.489237-1-umang.jain@ideasonboard.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c

@@ -245,7 +245,7 @@ find_service_by_handle(struct vchiq_instance *instance, unsigned int handle)
 		return service;
 	}
 	rcu_read_unlock();
-	vchiq_log_debug(service->state->dev, VCHIQ_CORE,
+	vchiq_log_debug(instance->state->dev, VCHIQ_CORE,
 			"Invalid service handle 0x%x", handle);
 	return NULL;
 }
@@ -287,7 +287,7 @@ find_service_for_instance(struct vchiq_instance *instance, unsigned int handle)
 		return service;
 	}
 	rcu_read_unlock();
-	vchiq_log_debug(service->state->dev, VCHIQ_CORE,
+	vchiq_log_debug(instance->state->dev, VCHIQ_CORE,
 			"Invalid service handle 0x%x", handle);
 	return NULL;
 }
@@ -310,7 +310,7 @@ find_closed_service_for_instance(struct vchiq_instance *instance, unsigned int h
 		return service;
 	}
 	rcu_read_unlock();
-	vchiq_log_debug(service->state->dev, VCHIQ_CORE,
+	vchiq_log_debug(instance->state->dev, VCHIQ_CORE,
 			"Invalid service handle 0x%x", handle);
 	return service;
 }