Use lib_get_stream() to fetch stdin/stdout/stderr,
since is more easy to works with other language by function call
than export native C structure memory layout.
Signed-off-by: Huang Qi <huangqi3@xiaomi.com>
This is preparation for flushing streams from user space, like it should
be done.
- Move tg_streamlist (group, kernel space) ->
ta_streamlist (TLS, user space)
- Access stream list via tg_info in kernel
- Access stream list via TLS in user space
- Remove / rename nxsched_get_streams -> lib_getstreams
- Remove system call for nxsched_get_streams