net: fq: Remove unused typedef fq_flow_get_default_t

Commitbf9009bf21b5 ("net/fq_impl: drop get_default_func, move default flow to fq_tin")
remove its last user, so can remove it.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230807142111.33524-1-yuehaibing@huawei.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>