musl: introduce wrappers for getopt() and getopt_long()
musl's getopt_long() behaves something different in handling optional arguments:
```
$ journalctl _PID=1 _COMM=systemd --since 19:19:01 -n all --follow
Failed to add match 'all': Invalid argument
```
This introduces getopt_long_fix() that reorders the passed arguments to make
getopt_long() provided by musl works as what we expect.
Also, musl's getopt() always behaves POSIXLY_CORRECT mode, and stops parsing
arguments when a non-option string found. Let's always use getopt_long().