/var/mail is used from /usr/include/paths.h if not set,
So set --with-path-mbox=/var/spool/mail to fix spoll path
from /var/mail to /var/spool/mail.
change libexec prefix --libexecdir=/usr/lib. So now full path
is /usr/lib/opensmtpd, not /usr/lib/opensmtpd/opensmtpd
remove post-install script. There is no need to run 'newaliases' because
in default config aliases table use file: driver, not db: driver
remove empty /usr/bin directory
in init-script explictly set 'name' and 'command' variables to not
be dependent on script name.