usb: xhci-mtk: fix leakage of shared hcd when fail to set wakeup irq

Can not set the @shared_hcd to NULL before decrease the usage count
by usb_put_hcd(), this will cause the shared hcd not released.

Fixes: 04284eb74e ("usb: xhci-mtk: add support runtime PM")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20221128063337.18124-1-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/xhci-mtk.c

@@ -646,7 +646,6 @@ static int xhci_mtk_probe(struct platform_device *pdev)
 
 dealloc_usb3_hcd:
 	usb_remove_hcd(xhci->shared_hcd);
-	xhci->shared_hcd = NULL;
 
 put_usb3_hcd:
 	usb_put_hcd(xhci->shared_hcd);