util-linux minor typo fixes

Signed-off-by: Gilles Espinasse <g.esp@free.fr>
tests: new warning fix

2.23 added -Wstrict-prototypes check. Fix make check showing
CC tests/helpers/test_md5.o
tests/helpers/test_md5.c:8: warning: function declaration isn't a prototype

Signed-off-by: Gilles Espinasse <g.esp@free.fr>
agetty: allow full control on CLOCAL flag

Now the -L option allows to explicitly enable CLOCAL flag.

Unfortunately sometimes it's necessary to clear the flag. This patch
add optional argument =<mode> to specify 'auto', 'always' and 'never'
to control CLOCAL flag.

Addresses: https://bugzilla.redhat.com/show_bug.cgi?id=816342
Signed-off-by: Karel Zak <kzak@redhat.com>