r8169: fix firmware not resetting tp->ocp_base

r8169: fix firmware not resetting tp->ocp_base

BugLink: https://bugs.launchpad.net/bugs/1885072
Typically the firmware takes care that tp->ocp_base is reset to its
default value. That's not the case (at least) for RTL8117.
As a result subsequent PHY access reads/writes the wrong page and
the link is broken. Fix this be resetting tp->ocp_base explicitly.

Fixes: 229c1e0dfd3d ("r8169: load firmware for RTL8168fp/RTL8117")
Reported-by: Aaron Ma <mapengyu@gmail.com>
Tested-by: Aaron Ma <mapengyu@gmail.com>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 89fbd26cca7ec9e82ec4787a4b6e95939b57d073)
Signed-off-by: Aaron Ma <aaron.ma@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>