Refactor: libcib: Support some formatted output in cib__signon_query()

Now cibsignon_query() can output the messages currently in
crm_mon.c:cib_connect() and pcmk_status.c:cib_connect(). This will be
useful soon when replacing some existing crm_mon logic with
cibsignon_query().

Signed-off-by: Reid Wahl <nrwahl@protonmail.com>