config: display key_delim for config --bool --get-regexp
The previous logic in show_config was to print the delimiter when the
value was set, but Boolean variables have an implicit value "true" when
they appear with no value in the config file. As a result, we got:
Fix this by defering the display of the separator until after the value
to display has been computed.
Reported-by: Brian Foster <brian.foster@maxim-ic.com> Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr> Signed-off-by: Junio C Hamano <gitster@pobox.com>