Fix some typos in the man page.

Signed-off-by: Andris Kalnozols <andris@hpl.hp.com>
Acked-by: Steffan Karger <steffan.karger@fox-it.com>
Message-Id: <53AF0D20.7020204@karger.me>
Signed-off-by: Gert Doering <gert@greenie.muc.de>