worker: remove unused wq_state

wq_state isn't used at all. It is non-sense to keep it in the code.

Signed-off-by: Liu Yuan <tailai.ly@taobao.com>
tracer: rework tracer to work with master

Signed-off-by: Liu Yuan <tailai.ly@taobao.com>
tracer: fix trace-cat commind for empty trace file

Signed-off-by: Liu Yuan <tailai.ly@taobao.com>
collie: use do_generic_subcommind in debug module

Signed-off-by: Liu Yuan <tailai.ly@taobao.com>