usb: xhci: wait for CNR controller not ready bit in xhci resume

NVIDIA 3.1 xHCI card would lose power when moving power state into D3Cold.
Thus we need to wait for CNR bit to clear in xhci resume, just as in
xhci init.

[Minor changes to comment and commit message -Mathias]
Cc: <stable@vger.kernel.org>
Signed-off-by: Rick Tseng <rtseng@nvidia.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/1570190373-30684-6-git-send-email-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>