[drivers]修复can驱动编译错误 (#7708)

bsp/imxrt/libraries/drivers/drv_can.c

@@ -430,7 +430,7 @@ static rt_ssize_t can_send(struct rt_can_device *can_dev, const void *buf, rt_ui
     return (rt_ssize_t)ret;
 }
 
-static int can_recv(struct rt_can_device *can_dev, void *buf, rt_uint32_t boxno)
+static rt_ssize_t can_recv(struct rt_can_device *can_dev, void *buf, rt_uint32_t boxno)
 {
     struct imxrt_can *can;
     struct rt_can_msg *pmsg;

components/drivers/include/drivers/can.h

@@ -351,8 +351,8 @@ struct rt_can_ops
 {
     rt_err_t (*configure)(struct rt_can_device *can, struct can_configure *cfg);
     rt_err_t (*control)(struct rt_can_device *can, int cmd, void *arg);
-    int (*sendmsg)(struct rt_can_device *can, const void *buf, rt_uint32_t boxno);
-    int (*recvmsg)(struct rt_can_device *can, void *buf, rt_uint32_t boxno);
+    rt_ssize_t (*sendmsg)(struct rt_can_device *can, const void *buf, rt_uint32_t boxno);
+    rt_ssize_t (*recvmsg)(struct rt_can_device *can, void *buf, rt_uint32_t boxno);
 };
 
 rt_err_t rt_hw_can_register(struct rt_can_device    *can,