r8169: rtl_csi_access_enable rename.

Newer 8168 needs a slightly different rtl_csi_access_enable.
This patch separates some noise from the real thing.

No functional change.

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