Merge branch 'net-tso-expand-to-UDP-support'

Eric Dumazet says:

====================
net: tso: expand to UDP support

With QUIC getting more attention these days, it is worth
implementing UDP direct segmentation, the same we did for TCP.

Drivers will need to advertize NETIF_F_GSO_UDP_L4 so that
GSO stack does not do the (more expensive) segmentation.

Note the two first patches are stable candidates, after
tests confirm they do not add regressions.

v2: addressed Jakub feedback :
   1) Added a prep patch for octeontx2-af
   2) calls tso_start() earlier in otx2_sq_append_tso()
====================

Signed-off-by: David S. Miller <davem@davemloft.net>