add "-headerpad_max_install_names" to OTHER_LDFLAGS for install_name_tool

Change-Id: Iaca0babcbf7ed47f29240f60aa6e72a1981aef55
Reviewed-on: http://review.couchbase.org/26803
Reviewed-by: Philip Labee <philip@couchbase.com>
Reviewed-by: Traun Leyden <tleyden@couchbase.com>
Tested-by: Traun Leyden <tleyden@couchbase.com>