The head member of struct pack_info is completely unused and the
nr_heads member is used only in one place, which is an assignment. This
member was last usefully used in 3e15c67c90 (server-info: throw away T
computation as well, 2005-12-04).
Since this structure member is not useful, remove it.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>