Since commit 7c3baa9 (help -a: do not unnecessarily look for a
repository, 2009-09-04), the help format that is passed as a
command line option is not used if an help format has been
configured. This patch fixes that.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>