SUNXI-GMAC driver logs every vlan frame...

Hello!

Don't know if i'm the only one who's using vlan with sunxi-gmac, but the
current driver is terribly spammy for the logs, it log every single vlan
frame at the INFO level. Personally i don't think that information is
useful at all but if you want to keep it enable, it should log it at the
DEBUG level instead. So i propose this little simple modification to the
source (or better, remove the whole line.):