um: NULL check before kfree is not needed

kfree(NULL) is safe,so this removes NULL check before freeing the mem
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

arch/um/drivers/vector_kern.c

@@ -1118,15 +1118,10 @@ static int vector_net_close(struct net_device *dev)
 		os_close_file(vp->fds->tx_fd);
 		vp->fds->tx_fd = -1;
 	}
-	if (vp->bpf != NULL)
 	kfree(vp->bpf);
-	if (vp->fds->remote_addr != NULL)
 	kfree(vp->fds->remote_addr);
-	if (vp->transport_data != NULL)
 	kfree(vp->transport_data);
-	if (vp->header_rxbuffer != NULL)
 	kfree(vp->header_rxbuffer);
-	if (vp->header_txbuffer != NULL)
 	kfree(vp->header_txbuffer);
 	if (vp->rx_queue != NULL)
 		destroy_queue(vp->rx_queue);

arch/um/drivers/vector_user.c

@@ -267,7 +267,6 @@ static struct vector_fds *user_init_raw_fds(struct arglist *ifspec)
 		os_close_file(rxfd);
 	if (txfd >= 0)
 		os_close_file(txfd);
-	if (result != NULL)
 	kfree(result);
 	return NULL;
 }
@@ -434,7 +433,6 @@ static struct vector_fds *user_init_socket_fds(struct arglist *ifspec, int id)
 	if (fd >= 0)
 		os_close_file(fd);
 	if (result != NULL) {
-		if (result->remote_addr != NULL)
 		kfree(result->remote_addr);
 		kfree(result);
 	}

arch/um/kernel/irq.c

@@ -244,7 +244,6 @@ static void garbage_collect_irq_entries(void)
 			to_free = NULL;
 		}
 		walk = walk->next;
-		if (to_free != NULL)
 		kfree(to_free);
 	}
 }