Fix: various: issues discovered via valgrind and coverity

• memory leak in crmd/join_dc.c:do_dc_join_ack()
• dead code in lib/services/services.c:resources_list_standards()
• hidden variables in attrd/commands.c:attrd_peer_update(), fencing/commands.c:handle_request(), pengine/main.c:pe_ipc_dispatch(), lib/cluster/cpg.c:pcmk_message_common_cs(), and lib/pengine/utils.c:resource_location()
• unused value in pengine/native.c:RecurringOp()