eth: fbnic: support setting RSS configuration

eth: fbnic: support setting RSS configuration

Let the user program the RSS indirection table and the RSS key.
Straightforward implementation. Track the changes and don't bother
poking the HW if user asked for a config identical to what's already
programmed. The device only supports Toeplitz hash.

Similarly to the GET support - all the real code that does the programming
was part of initial driver submission, already.

Signed-off-by: Alexander Duyck <alexanderduyck@fb.com>
Link: https://patch.msgid.link/20241220025241.1522781-5-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>