driver core: add missing blank line after declaration

Found using checkpatch.pl
Signed-off-by: Lavinia Tache <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/base/driver.c

···
 		       const struct driver_attribute *attr)
 {
 	int error;
+
 	if (drv)
 		error = sysfs_create_file(&drv->p->kobj, &attr->attr);
 	else