fdo#75757: remove inheritance to std::map

Typedef'ing AcceptorMap in appinit.cxx is enough.

Change-Id: Ia26e119562c87b11d8dd81f49b72d825739162b2
Reviewed-on: https://gerrit.libreoffice.org/10555
Reviewed-by: David Tardon <dtardon@redhat.com>
Tested-by: David Tardon <dtardon@redhat.com>