fou: Remove IPPROTO_UDPLITE check in gue_err() and gue6_err().

fou: Remove IPPROTO_UDPLITE check in gue_err() and gue6_err().

UDP-Lite has been removed, and its error handler is no
longer found in either inet_protos[IPPROTO_UDPLITE] or
inet6_protos[IPPROTO_UDPLITE].

The recursion fixed by the protocol check in gue_err()
and gue6_err() no longer occurs with UDP-Lite.

Let's remove the checks.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Joe Damato <joe@dama.to>
Link: https://patch.msgid.link/20260316133127.2646421-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>