staging: greybus: power_supply: replace kzalloc by kcalloc

According to checkpatch.pl, kcalloc should be preferred to kzalloc with
multiply.
Signed-off-by: JB Van Puyvelde <jbvanpuyvelde@gmail.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Rui Miguel Silva <rmfrfs@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/greybus/power_supply.c

@@ -944,7 +944,7 @@ static int gb_power_supplies_setup(struct gb_power_supplies *supplies)
 	if (ret < 0)
 		goto out;
 
-	supplies->supply = kzalloc(supplies->supplies_count *
+	supplies->supply = kcalloc(supplies->supplies_count,
 				     sizeof(struct gb_power_supply),
 				     GFP_KERNEL);