add n32g45x can 驱动

bsp/n32g452xx/Libraries/rt_drivers/drv_can.h

+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2022-01-09     chenbin      the first version
+ */
+
+#ifndef __DRV_CAN_H__
+#define __DRV_CAN_H__
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <board.h>
+#include <rtdevice.h>
+#include <rtthread.h>
+
+int rt_hw_can_init(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /*__DRV_CAN_H__ */
+
+/************************** end of file ******************/