Merge branch 'r8169-improve-rtl_rx-and-NUM_RX_DESC-handling'

Heiner Kallweit says:

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r8169: improve rtl_rx and NUM_RX_DESC handling

This series improves rtl_rx() and the handling of NUM_RX_DESC.
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Signed-off-by: David S. Miller <davem@davemloft.net>