can: proc: remove unnecessary variables

There is no need to define the variable "rate" to receive, just return
directly.

Link: https://lore.kernel.org/r/20210514100806.792-1-zuoqilin1@163.comSigned-off-by: zuoqilin <zuoqilin@yulong.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

net/can/proc.c

@@ -99,8 +99,6 @@ static void can_init_stats(struct net *net)
 static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
 			       unsigned long count)
 {
-	unsigned long rate;
-
 	if (oldjif == newjif)
 		return 0;
 
@@ -111,9 +109,7 @@ static unsigned long calc_rate(unsigned long oldjif, unsigned long newjif,
 		return 99999999;
 	}
 
-	rate = (count * HZ) / (newjif - oldjif);
-
-	return rate;
+	return (count * HZ) / (newjif - oldjif);
 }
 
 void can_stat_update(struct timer_list *t)