net_sched: fold tcf_block_cb_call() into tc_setup_cb_call()

After commit 69bd4840 ("net/sched: Remove egdev mechanism"),
tc_setup_cb_call() is nearly identical to tcf_block_cb_call(),
so we can just fold tcf_block_cb_call() into tc_setup_cb_call()
and remove its unused parameter 'exts'.

Fixes: 69bd4840

 ("net/sched: Remove egdev mechanism")
Cc: Oz Shlomo <ozsh@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>