[RFC] r8169 : why SG / TX checksum are default disabled

Hi Francois

I was wondering why Scatter Gather (NETIF_F_SG) and TX checksum
(NETIF_F_IP_CSUM) were disabled by default on r8169.

Couldnt we enable them by default, maybe for a whitelist of "good"
nics ?

(I found that activating them with ethtool automatically enables GSO,
 and performance with GSO is not good)

Thanks