rtl8192cu: Fix unbalanced irq enable in error path of rtl92cu_hw_init()

Fixes: a53268be ('rtlwifi: rtl8192cu: Fix too long disable of IRQs')
Cc: stable@vger.kernel.org
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/rtlwifi/rtl8192cu/hw.c

@@ -1001,7 +1001,7 @@ int rtl92cu_hw_init(struct ieee80211_hw *hw)
 	err = _rtl92cu_init_mac(hw);
 	if (err) {
 		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG, "init mac failed!\n");
-		return err;
+		goto exit;
 	}
 	err = rtl92c_download_fw(hw);
 	if (err) {