r8169:Remove unnecessary phy reset for pcie nic when setting link spped.

For pcie nic, after setting link speed and there is no link driver does not need
to do phy reset until link up.

For some pcie nics, to do this will also reset phy speed down counter and prevent
phy from auto speed down.

This patch fix the issue reported in following link.
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1547151

Signed-off-by: Chunhao Lin <hau@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>