workqueue: remove deprecated WQ_NON_REENTRANT

Tejun Heo has made WQ_NON_REENTRANT useless in the dbf2576e37
("workqueue: make all workqueues non-reentrant"). So remove its
usages and definition.

This patch doesn't introduce any behavior changes.

tj: minor description updates.

Signed-off-by: ZhangZhen <zhenzhang.zhang@huawei.com>
Sigend-off-by: Tejun Heo <tj@kernel.org>
Acked-by: James Chapman <jchapman@katalix.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/dw_mmc.c

@@ -2607,7 +2607,7 @@ int dw_mci_probe(struct dw_mci *host)
 
 	tasklet_init(&host->tasklet, dw_mci_tasklet_func, (unsigned long)host);
 	host->card_workqueue = alloc_workqueue("dw-mci-card",
-			WQ_MEM_RECLAIM | WQ_NON_REENTRANT, 1);
+			WQ_MEM_RECLAIM, 1);
 	if (!host->card_workqueue) {
 		ret = -ENOMEM;
 		goto err_dmaunmap;