a control variable was misspelled as `SCRIPTS_NAME_isdntel.sh'
(should've been `SCRIPTSNAME_isdntel.sh') when the Makefile was
converted to using <bsd.prog.mk>. Consequently, `isdntel.sh' has
been installed as `isdntel' since then. Nevertheless, nobody has
been unhappy with the change. So it's time to make it official.
Approved by: hm
Pointy hat to: ru
MFC after: 3 days
a227277a6d