tools: Reformat --help output of virsh and virt-admin

tools: Reformat --help output of virsh and virt-admin

The --help output of virsh and virt-admin shows supported options
and commands and as such contains new lines. Both these strings
are marked for translation btw. But the way they are formatted
now ('\n' being at the start of new line instead at the end of
the previous) makes it hard to create a syntax-check rule for
'translation message on one line' (next commit).

Reformat both strings a bit (no user visible change though).

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>