Fix spelling of command line/command-line

Fix spelling of command line/command-line

Commandline/command line/command-line where being used interchangeably,
which is not correct
(see: https://learn.microsoft.com/en-us/style-guide/a-z-word-list-term-collections/c/command-line).
use command-line when it is an adjective (e.g. "command-line interface")
and use command line when it is a noun (e.g. "change the setting from
the command line")

Signed-off-by: Noel Ullreich <n.ullreich@proxmox.com>
[S.I.: fix a stray ' ' introduced with this commit]
Signed-off-by: Stoiko Ivanov <s.ivanov@proxmox.com>