Merge branch 'sfc-ef100-tso-enhancements'

Edward Cree says:

====================
sfc: EF100 TSO enhancements

Support TSO over encapsulation (with GSO_PARTIAL), and over VLANs
 (which the code already handled but we didn't advertise).  Also
 correct our handling of IPID mangling.

I couldn't find documentation of exactly what shaped SKBs we can
 get given, so patch #2 is slightly guesswork, but when I tested
 TSO over both underlay and (VxLAN) overlay, the checksums came
 out correctly, so at least in those cases the edits we're making
 must be the right ones.
Similarly, I'm not 100% sure I've correctly understood how FIXEDID
 and MANGLEID are supposed to work in patch #3.
====================

Link: https://lore.kernel.org/r/6e1ea05f-faeb-18df-91ef-572445691d89@solarflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>