If the local receiving repository has disabled the use of delta base
offset, for example to retain compatibility with older versions of
Git that predate OFS_DELTA, we shouldn't ask for ofs-delta support
when we obtain a pack from the remote server.
[ issue noticed by Shawn Pearce ]
Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>