Merge changes from topic "CVE-2020-1712" into tizen

Merge changes from topic "CVE-2020-1712" into tizen

* changes:
  Fix typo in function name
  man: document the new sd_bus_enqueue_for_read() API call
  polkit: when authorizing via PK let's re-resolve callback/userdata instead of caching it
  sd-bus: introduce API for re-enqueuing incoming messages
  polkit: use structured initialization
  polkit: on async pk requests, re-validate action/details
  polkit: reuse some common bus message appending code
  bus-polkit: rename return error parameter to ret_error
  shared: split out polkit stuff from bus-util.c → bus-polkit.c