All options started with underscores, but we switched them to dashes
later on, making the style consistent.  The latest addition, however,
did not respect that, so let's change that as well.  It is tempting to
just change the name instead of adding alias, especially since nobody
ever used it, which we know thanks to the fact that it didn't work.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>