net: rtlwifi: properly check for alloc_workqueue() failure

If alloc_workqueue() fails, properly catch this and propagate the error
to the calling functions, so that the devuce initialization will
properly error out.

Cc: Kalle Valo <[e-mail]>
Cc: Bryan Brattlof <[e-mail]>
Cc: stable <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/net/wireless/realtek/rtlwifi/base.c

···
 static void rtl_fwevt_wq_callback(struct work_struct *work);
 static void rtl_c2hcmd_wq_callback(struct work_struct *work);
 
-static void _rtl_init_deferred_work(struct ieee80211_hw *hw)
+static int _rtl_init_deferred_work(struct ieee80211_hw *hw)
 {
 	struct rtl_priv *rtlpriv = rtl_priv(hw);
+	struct workqueue_struct *wq;
+
+	wq = alloc_workqueue("%s", 0, 0, rtlpriv->cfg->name);
+	if (!wq)
+		return -ENOMEM;
 
 	/* <1> timer */
 	timer_setup(&rtlpriv->works.watchdog_timer,
···
 		    rtl_easy_concurrent_retrytimer_callback, 0);
 	/* <2> work queue */
 	rtlpriv->works.hw = hw;
-	rtlpriv->works.rtl_wq = alloc_workqueue("%s", 0, 0, rtlpriv->cfg->name);
+	rtlpriv->works.rtl_wq = wq;
+
 	INIT_DELAYED_WORK(&rtlpriv->works.watchdog_wq,
 			  rtl_watchdog_wq_callback);
 	INIT_DELAYED_WORK(&rtlpriv->works.ips_nic_off_wq,
···
 			  rtl_swlps_rfon_wq_callback);
 	INIT_DELAYED_WORK(&rtlpriv->works.fwevt_wq, rtl_fwevt_wq_callback);
 	INIT_DELAYED_WORK(&rtlpriv->works.c2hcmd_wq, rtl_c2hcmd_wq_callback);
+	return 0;
 }
 
 void rtl_deinit_deferred_work(struct ieee80211_hw *hw, bool ips_wq)
···
 	rtlmac->link_state = MAC80211_NOLINK;
 
 	/* <6> init deferred work */
-	_rtl_init_deferred_work(hw);
-
-	return 0;
+	return _rtl_init_deferred_work(hw);
 }
 EXPORT_SYMBOL_GPL(rtl_init_core);