net: wan: lmc: use time_is_before_jiffies() instead of open coding it

Use the helper function time_is_{before,after}_jiffies() to improve
code readability.
Signed-off-by: Wang Qing <wangqing@vivo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wan/lmc/lmc_main.c

@@ -57,6 +57,7 @@
 #include <asm/io.h>
 #include <asm/dma.h>
 #include <linux/uaccess.h>
+#include <linux/jiffies.h>
 //#include <asm/spinlock.h>
 
 #define DRIVER_MAJOR_VERSION     1
@@ -1968,7 +1969,7 @@ static void lmc_driver_timeout(struct net_device *dev, unsigned int txqueue)
     printk("%s: Xmitter busy|\n", dev->name);
 
     sc->extra_stats.tx_tbusy_calls++;
-    if (jiffies - dev_trans_start(dev) < TX_TIMEOUT)
+    if (time_is_before_jiffies(dev_trans_start(dev) + TX_TIMEOUT))
 	    goto bug_out;
 
     /*