Merge branch 'r8169-revert-two-commits-due-to-a-regression'

Heiner Kallweit says:

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r8169: revert two commits due to a regression

Sander reported a regression (kernel panic, see[1]), therefore let's
revert these commits. Removal of the barriers doesn't seem to
contribute to the issue, the patch just overlaps with the problematic
one and only reverting both patches was tested.

[1] https://marc.info/?t=154965066400001&r=1&w=2

v2:
- improve commit message
====================

Signed-off-by: David S. Miller <davem@davemloft.net>