TSO requires tx checksumming. For non GSO frames in TSO/EDDP mode we
have to manually calculate the checksum.
Signed-off-by: NFrank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: NUrsula Braun <braunu@de.ibm.com>
Signed-off-by: NJeff Garzik <jeff@garzik.org>