allow name_bind so mpd can open it's port

Apr  4 19:33:33 maelstrom kernel: [ 3916.408373] type=1400 audit(1396632813.986:482): avc:  denied  { name_bind } for  pid=16949 comm="mpd" src=6600 scontext=staff_u:staff_r:staff_t tcontext=system_u:object_r:mpd_port_t tclass=tcp_socket