r8169: workaround for missing extended GigaMAC registers

GigaMAC registers have been reported left unitialized in several
situations:
- after cold boot from power-off state
- after S3 resume

Tweaking rtl_hw_phy_config takes care of both.

This patch removes an excess entry (",") at the end of the exgmac_reg
array as well.

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