syscalls/abort01: code cleanups

Cleanup the code.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
syscalls/accept01: code cleanups

Cleanup the code.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
syscalls/accept4_01: code cleanups

Cleanup the code.

Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>