find_inferior (&all_lwps) -> iterate_over_lwps

[Yao Qi]

Hi,
GDB needs "pause_all/unpause_all" in GDBserver to control threads
correctly when talking with IPA.  Some callbacks are available in
GDBserver, and GDB can simply 'use' them.  However, GDB and GDBserver
has the different way to iterate over 'lwp_info' (iterate_over_lwps vs
find_inferior), and prevent GDB using these callbacks in GDBserver.

What I want to do is to 'replace find_inferior (&all_lwps) with
iterate_over_lwps in GDBserver', which makes share more code on both
sides easier.  What do you think?

-- 
Yao (齐尧)