rtlwifi: rtl_pci_probe: Fix fail path of _rtl_pci_find_adapter

_rtl_pci_find_adapter fail path will jump to label fail3 for
unsupported adapter types.

However, on course for fail3 there will be call rtl_deinit_core
before rtl_init_core.

For the inclusion of checking pci_iounmap this fail can be moved to
fail2.

Fixes
[    4.492963] BUG: unable to handle kernel NULL pointer dereference at           (null)
[    4.493067] IP: rtl_deinit_core+0x31/0x90 [rtlwifi]
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

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

@@ -2257,7 +2257,7 @@ int rtl_pci_probe(struct pci_dev *pdev,
 	/* find adapter */
 	if (!_rtl_pci_find_adapter(pdev, hw)) {
 		err = -ENODEV;
-		goto fail3;
+		goto fail2;
 	}
 
 	/* Init IO handler */
@@ -2318,10 +2318,10 @@ int rtl_pci_probe(struct pci_dev *pdev,
 	pci_set_drvdata(pdev, NULL);
 	rtl_deinit_core(hw);
 
+fail2:
 	if (rtlpriv->io.pci_mem_start != 0)
 		pci_iounmap(pdev, (void __iomem *)rtlpriv->io.pci_mem_start);
 
-fail2:
 	pci_release_regions(pdev);
 	complete(&rtlpriv->firmware_loading_complete);