r8169: replace magic numbers with PCI MRRS constant

Replace magic number "0x5 << MAX_READ_REQUEST_SHIFT" with the
appropriate constant as defined in PCI core.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed