r8169 : MAC address change fix for the 8168e-vl.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=39252



Hayes suggested that the usual MAC{0, 4} register writes be completed
with writes to extended GigaMAC registers :
- 0xe0 .. 0xe5
- 0xf2 .. 0xf7

Registers 0xf0 and 0xf1 should be set to 0.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>