sfc: update EF10 register definitions

The RX_L4_CLASS field has shrunk from 3 bits to 2 bits. The upper
bit was never used in previous hardware, so we can use the new
definition throughout.

The TSO OUTER_IPID field was previously spelt differently from the
external definitions.

Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>