Looked a man page in work dir, it has correct path instead of
placeholder.
Before:
```
-f file Specify an alternative configuration file. By default,
tmux loads the system configuration file from
@SYSCONFDIR@/tmux.conf, if present, then looks for a user
configuration file at ~/.tmux.conf.
```
After:
```
-f file Specify an alternative configuration file. By default,
tmux loads the system configuration file from
/usr/local/etc/tmux.conf, if present, then looks for a user
configuration file at ~/.tmux.conf.
```